BEIRUT – The head of the U.N. observers’ mission in Syria demanded Sunday that warring parties allow the evacuation of women, children, elderly and sick people endangered by fighting in the besieged city of Homs and other combat zones.

Maj. Gen. Robert Mood said the observers had been trying for the past week to bring out families and wounded trapped in Homs by heavily shelling of rebel-held areas. The offensive is part of a broader push by President Bashar Assad’s forces to regain rebel-held villages and towns.

“The parties must reconsider their position and allow women, children, the elderly and the injured to leave conflict zones without any preconditions and ensure their safety,” Mood said in a statement. U.N. “attempts to extract civilians from the line of fire over the past week have been unsuccessful.”