UNITED NATIONS — International envoy Kofi Annan told the U.N. Security Council on Tuesday that the situation in Syria is “bleak,” and expressed alarm at reports that government troops are still carrying out military operations in towns where U.N. observers are not present.

He expressed particular concern at media reports that government troops entered the central city of Hama on Monday after U.N. observers departed, firing automatic weapons and killing a significant number of people. “If confirmed, this is totally unacceptable and reprehensible,” he said.

The joint U.N.-Arab League envoy said the speedy deployment of the 300-strong U.N. observer force authorized by the council on Saturday is “crucial” to verify what is happening on the ground. The observer force also would provide a basis for moving toward a cease-fire by the government and opposition, he said.