President Bukele declared a “war on gangs” last March, passing emergency measures which have been extended several times.
The emergency powers have been controversial as they limit some constitutional rights, such as allowing the security forces to arrest suspects without a warrant.
More than 64,000 suspects have been arrested in the anti-crime drive.
Authorities have said criminal gangs such as MS-13 and Barrio-18 number tens of thousands and are responsible for homicides, extortion and drug-trafficking. The aim of the mass arrests is to make the gangs “disappear altogether”, the government says.