The wave of detentions is unprecedented in the country of 6.5 million people, which has suffered decades of violent crime driven by powerful gangs such as Mara Salvatrucha (MS-13) and Barrio 18.
Police in El Salvador have arrested tens of thousands of suspected gang members since President Nayib Bukele declared a "war" on criminal groups seven months ago
"There have been more than 55,000 captures" of alleged gang members since March, when the government was handed emergency powers to arrest such suspects without a warrant, Minister of Justice Gustavo Villatoro said on Friday.
The number of arrests comes on top of some 16,000 that had already been made before the emergency powers were granted.
"We are winning the war (against organised crime) and we will continue to deploy thousands of police and soldiers every day to arrest these terrorists," Villatoro said as he sought the seventh extension of the emergency powers.
Police and military forces have seized 1,644 firearms, 2,026 vehicles, 12,842 cell phones and $1.2 million, Villatoro added.
To cope with an influx of inmates, El Salvador's judicial authorities are building a huge prison for 40,000 suspected criminals in Tecoluca, a rural area in the centre of the country.
The detention centre is expected to be completed by the end of the year.
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