The Brazilian Navy’s Combat Divers Group (Grupamento de Mergulhadores de Combate – GRUMEC) is arguably one of South America’s most capable and specialised units. Often nicknamed “Brazilian Navy SEALs”, it is also comparable to the British Special Boat Service and the French SBS. Brazil’s geographical and military needs shape this force. This makes it a unique unit that combines special warfare with the local aquatic environments, involving both sea, rivers, and wetlands.
Very little operation background is available in public sources. Nonetheless, we know that their versatility has led to their involvement in domestic counterterrorism operations during high-security events (e.g. Olympics and FIFA World Cup) as well as international peacekeeping missions (e.g. MINUSTAH and UNIFIL). Although their origin involved inter-military cooperation, their intensive and challenging training is now managed domestically. Talking of GRUMEC means addressing one of the most secretive, elite, and rapid-responsive special operations units on the continent.
Images Sourced From: Marinha do Brasil,
1 GRUMEC – Operational Footprint
As the elite special operations unit of the Brazilian Navy, GRUMEC engages in high-risk amphibious and maritime missions. Their operations include intelligence collection, capture of enemies, rescue missions, sabotage, infiltration, and bombing of underwater objectives. Over the past twenty years, they have become more relevant to Brazil’s strategic and security posture.
Although often compared to the U.S. Navy SEALs, their identity is quite distinct. Their focus on maritime and riverine operations is crucial, alongside joint missions with other of Brazil’s military branches. As one could expect, their operational record is mostly classified. Nonetheless, their involvement in various operations and missions is publicly acknowledged.
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1.1 Domestic Missions
Domestically, GRUMEC conducted, as reported by MB Commander Michael Vinicius Aguiar, reconnaissance, monitoring, and counterterrorism in large public events such as the 2014 FIFA World Cup and the 2016 Rio Summer Olympic Games. Those specific responsibilities were undertaken by a specialized team within GRUMEC, the Special Rescue and Recovery Group. In both events, the units cooperated with the Brazilian Armed Forces and the Civil and Military Police. Furthermore, there are reports of their involvement in river operations across the Amazon and Pantanal regions. It is evident that their capabilities suit operations in those environments. Areas such as the Amazon tri-border prove difficult to govern and control, and illicit activities are widespread there, making it an ideal terrain for GRUMEC deployment.
1.2 International Missions
GRUMEC’s role in the United Nations Stabilization Mission in Haiti (MINUSTAH) is one of its most significant moments of international involvement. So is their participation in the United Nations Interim Force in Lebanon (UNIFIL). In both cases, GRUMEC was tasked with specifically maritime security and support. The two missions increased their real-world operational experience and placed them in the security landscape as a reliable partner in international peacekeeping.
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2 GRUMEC – Structure
The internal structure of the GRUMEC group is strictly classified. It is said to be comprised of three operational units and a Special Rescue and Recovery Group (GERR-MEC)
The structure is designed for it to be ready and versatile, a necessity given the wide array of missions that they are capable of carrying out. Structurally, they officially work under the Submarine Force Command (Comando da Força de Submarinos), which provides the institutional and logistical support that the highly specialized group needs. Nonetheless, they maintain a great degree of independence and autonomy, as is suitable for a special operations group such as GRUMEC.
The Special Rescue and Recovery Group subdivision of GRUMEC (Grupo Especial de Retomada e Resgate de Mergulhadores de Combate – GERR-MEC) is worth separate mention. To access the group, one must serve in GRUMEC for at least two years. This group works in rapid intervention situations, such as hostage and vessel rescues. They also act in situations of maritime installations rescue, petrol platform rescue, and anti-terrorism. The group was active during the 2014 FIFA World Cup and the 2016 Rio Olympics in coordination with other police and army units.
3 GRUMEC – History
3.1 Cross-National Input
The origins of GRUMEC trace back to 1964. In that period, following some training abroad, officers of the Brazilian Navy sought to develop similar capabilities to those of the North Americans and French in the field. The first step towards the structural creation of what would become GRUMEC was the creation, in 1970, of the Combat Divers Division (Divisão de Mergulhadores de Combate). In the following years, there was continuous collaboration with French forces, which trained soldiers and officers for the division.
3.2 Domestic Development
The first locally provided special training started in 1974, with the Special Course for Combat Divers (Curso Especial de Mergulhador de Combate – C-ESP-MEC) provided by the Submariners School (Escola de Submarinos). It was only in 1983 that the group became a formal military unit. In 1998, the unit finally assumed its current name as the Navy’s Combat Divers Group (Grupamento de Mergulhadores de Combate – GRUMEC). At the time, the group was placed under the authority of the Submarine Force Command (Comando da Força de Submarinos), where it sits today.
4 The Training Regime
Becoming a GRUMEC member is likely the most challenging and difficult process within the Brazilian Armed Forces. The core training of this unit is the Special Course for Combat Divers (Curso Especial de Mergulhador de Combate – C-ESP-MEC). It is nowadays offered by the Centro de Instrução e Adestramento Almirante Áttila Monteiro Aché (CIAMA). The official training span lasts, across all phases, around 45 weeks. MB Commander Michael Vinicius Aguiar once joked in an interview that the course is “the length of a pregnancy.” Very few of the candidates actually complete the course. Reports from August 2024 claim only 240 individuals completed it across 39 years, with certain training rounds in which no candidate successfully graduated.
4.1 Training Phases (ALPHA, BRAVO, CHARLIE)
Only male applicants below the age of thirty are allowed to join the training process. The pre-screening tests consist of psychometric, health, and psychical aptitude tests. Among the prerequisites to join the training is a one-year deployment on Navy ships (previously two-years), and the rank of second lieutenant. Following this, from the available knowledge, we understand that the process is divided into three phases: ALPHA, BRAVO, and CHARLIE. Step ALPHA consists of a pre-selection and physical test, leading into basic diving training. Most applicants are filtered out at this stage. Those who pass the initial filter continue to the second step. The second step, BRAVO, consists of Special Operations training in both land and water environments, including both theoretical and practical training. Finally, step CHARLIE, the shortest and fullest of practical applications, involves specialized training in river operations, mountaineering, and combat techniques.
At the end of their training, GRUMEC divers are competent in the use of not only basic diving equipment, but also parachutes, inflatable support vessels, boats, kayaks, submarine vehicles, weapons and explosives. Furthermore, they are prepared in combat techniques, operational-tactical diving, demolition techniques, military intelligence, communication systems, and counterterrorism and counterinsurgency tactics.
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5 Conclusions
GRUMEC has evolved significantly since its origin as a small combat division, becoming the most innovative and specialized military unit in the country. Furthermore, one can consider GRUMEC as a mirror of Brazilian ambition to operate more effectively in maritime and riverine environments. Whether we are talking about securing water reserves in the Amazon area or protecting petrol platforms in their offshore “pre-salt” extraction sites, GRUMEC’s specialization matches national interests and security needs.
The group possesses capabilities that facilitate operational successes in contexts in which traditional military tools would normally fail. Although the operational record is hard to access, as it is mostly classified, available knowledge shows versatility and efficiency across different mission typologies. We acknowledge that the publication of further operational data may significantly alter our limited assessment of this elite unit.