( CNN ) -- Mexico 's military has notched an important success for President Felipe Calderon with the arrest of Jorge Eduardo Costilla Sanchez , the reputed boss of the powerful Gulf drug cartel . Costilla , nicknamed `` El Coss , '' was captured without a fight in the coastal city of Tampico , in the border state of Tamaulipas , Navy spokesman Jose Luis Vergara said Thursday . Wednesday 's arrest -- together with the seizure of weapons , vehicles and jewels -- is a much needed achievement for Calderon , whose offensive against drug cartels has done little to stem drug-related violence or the volume of drugs transported through Mexico . The mustachioed Costilla , handcuffed and wearing a checkered long-sleeve shirt under a bulletproof vest , was presented before reporters . Mexican marines chased a vehicle of armed men into a residence in Tampico , where they `` surprised '' Costilla and arrested him , Vergara said . Costilla is said to head a criminal group considered the third-most powerful in Mexico . `` El Coss is an important actor , '' said George Grayson , professor of government at the College of William & Mary and expert of drug cartels . `` His capture is a tremendous blow to the Gulf cartel . '' Five others were arrested with Costilla , and of five of his bodyguards were arrested after a shootout in a separate city , Vergara said . Some of them wore camouflage uniforms when they were presented next to Costilla . There are rewards in Mexico and the United States for Costilla 's arrest . Costilla has been indicted in the United States , accused of drug trafficking and threatening U.S. law enforcement officials in November 1999 . In that incident , according to the U.S. State Department , Costilla and other suspected Gulf Cartel leaders allegedly stopped federal agents and pointed AK-47 rifles at them . The agents were allowed to leave after a standoff . The State Department offered a reward of up to $ 5 million for information leading to Costilla 's arrest . In Mexico , where Costilla is on the government 's list of the 37 most-wanted traffickers , officials offered more than $ 2 million for his capture . While not as powerful as it once was , the Gulf Cartel is one of Mexico 's major drug trafficking organizations . Costilla assumed a top role after the arrest of former Gulf Cartel boss Osiel Cardenas Guillen and became the top leader after a rift with Cardenas ' relatives in the organization , authorities have said . As Costilla rose in the cartel hierarchy , the group controlled smuggling routes in northeastern Mexico by using its enforcement arm , known as Los Zetas , authorities have said . But Los Zetas later split into its own violent cartel , and for several years has been fighting the Gulf Cartel for the lucrative turf . `` El Coss survived internal divisions and directed violent confrontations in Tamaulipas and Nuevo Leon against his former allies , Los Zetas , '' Vergara said . The arrest is the latest in a series of blows against the Gulf Cartel , based in the city of Matamoros , across the border from Brownsville , Texas . This month , Mario Cardenas Guillen , reputed leader of the Gulf faction loyal to the Cardenas family , was also arrested by the military . Costilla 's arrest was the result of `` intense intelligence '' work by the Navy , and information gleaned from Mario Cardenas ' arrest , Vergara said . The rival Zetas , who operate in the same northeastern part of the country , may seem poised to take advantage of their rival 's vulnerability . But Grayson said internal divisions within the Zetas will prevent them from turning the heat up on the Gulf cartel , and that the Sinaloa cartel will be the trafficking group most likely to strengthen its position . In the past , surges in violence have been recorded after the killing or capture of cartel bosses . Internal rifts within the Gulf cartel and Zetas could lead to fights and alliances in a `` kaleidoscope situation , '' Grayson said . The other big winner is the Mexican Navy and its marines , who again proved they are effective at going after high-profile targets , he said . In 2009 , the marines were responsible for another of the Calderon administration 's biggest gets when they killed kingpin Arturo Beltran Leyva in a shootout . The U.S. Drug Enforcement Administration has provided intelligence to Mexican authorities during several operations , including the one that brought an end to Beltran Leyva . But the arrest of Costilla was a `` Mexican operation , '' said the U.S. drug agency 's spokesman , Rusty Payne . `` Obviously when a major cartel leader is arrested and brought to justice , it is significant . DEA congratulates the government of Mexico and their brave military for their continued success in apprehending top drug traffickers , '' Payne said .
NEW : This was a Mexican operation , the DEA says . Comment: Costilla is said to be the leader of the Gulf Cartel . Multimillion-dollar rewards were offered for his capture in Mexico and the United States .