Police and soldiers in El Salvador raided parts of the capital on Tuesday under a new campaign to break the reign of vicious gangs, officials said.

The operation marked another move by the government to squeeze the gangs who have helped make the Central American nation infamous as the world's deadliest country outside of a war zone.

Last week, authorities launched an elite Special Reaction Force of 1,000 police and troops to hunt gang leaders trying to take refuge in remote rural area and mountains.

And last month, a new law was brought in to isolate jailed gang bosses and to block cellphone signals from their prisons to prevent them giving orders to their followers.

Tuesday's raids were carried out by another new taskforce made up of 800 police officers and soldiers focused on urban missions. Its units are known as the Interventional and Territorial Recovery Forces, or FIRT under the Spanish acronym.

"On this day starts the plan to recover territory with the firm conviction to bring back security and calm for the population," said the military commander for the operation in San Salvador's northern La Campanera neighborhood, Colonel David Moreno.

He explained that soldiers set up perimeters to trap gang members while police carried out surprise raids inside it with warrants to catch suspected criminals.

The FIRT were being deployed to 81 districts in the 10 cities and towns with the highest incidence of gang violence, national police chief Howard Cotto said.

El Salvador has homicide rate of 104 per 100,000 inhabitants. There are around 22 murders a day.

Most of the bloodshed is blamed on the vicious gangs, many of whom arrived here are being deported from the United States during the 1990s.