A group of 38 male evacuees from besieged parts of the Syrian city of Homs were released Friday after investigation, leaving almost 200 others still being held, the provincial governor said.

The men and boys were among those detained by security services for questioning after being evacuated from the Old City of Homs by the UN and Red Crescent under a deal including a temporary ceasefire.

"They left the (processing) centre to the places they wanted to go to after their situations were resolved," governor Talal Barazi said of the 38 evacuees.

He told AFP that around 195 evacuees were still being held at the processing centre while investigations into their identity papers and military service status were being carried out.

The United Nations said earlier this week that some 380 male evacuees were still being held in processing centres, though it said some had been cleared for release but not yet left.

Barazi said many of the detainees were eager to take advantage of an amnesty offered last year to those who had failed to report for compulsory military service.

"Detainees have told us about their desire to settle their situations before being released because they were unable to take advantage of the amnesty while they were under siege," Barazi said.

He said evacuees over 42 would be automatically cleared because they were over the age for compulsory military service.

Beginning February 7, the United Nations and Red Crescent evacuated some 1,400 people trapped in besieged parts of Homs for more than 18 months as the Syrian regime battles rebels across the country.

Food was also delivered to those remaining behind, who had been forced to subsist on little more than olives and wild herbs.

All men and boys aged between 15-55 were taken for processing by security services, in a move that raised the concern of UN officials.

They are present at the processing centre and have warned that the operation is being carefully monitored.

The evacuations and delivery of aid were made possible by a deal that included a tenuous truce that was twice extended but expired last Saturday with no agreement to extend it further.

On Wednesday, Barazi said a group of 11 civilians had been evacuated from part of Homs, but operations have otherwise largely ground to a halt.

The UN has said it is focusing on the processing of male evacuees before any additional evacuation or aid distribution operations resume.

"The UN is taking a pause to plan for the next round of evacuations given that a significant number of civilians in the Old City of Homs are reported to be more vulnerable and frail," UN humanitarian coordinator Yacoub El-Hillo told AFP.

"The focus of UN activities currently remains on providing protection services to evacuees -- men and boys -- as they are processed by authorities."