A tip off to the police on Thursday evening led to them discovering four foreign nationals in Triq il-Barbagann, San Gwann, the police said.
The police said they went to a private residence where the men were indicated to be and searches resulted in four men, all Libyans, being found. They did not have any documents or permits to stay in Malta.
The men are aged 26, 29, 31 and 32.