The head of a U.N. observer team says that no amount of observers in Syria can achieve a permanent end to the violence without dialogue.

Norwegian team leader Maj. Gen. Robert Mood is calling for an end to the violence so that the mission can build on talks between the parties.

He spoke at a news conference in the Syrian capital on Friday.

More than 200 observers are currently deployed in various towns and cities around Syria to monitor a cease-fire brokered by international peace envoy Kofi Annan, but violations are reported by both sides every day.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

BEIRUT (AP) — Opposition groups say Syrian government forces are pounding a rebel-held town north of the central city of Homs.

The shelling is part of an offensive that has been going on for days as the regime tries to retake the town of Rastan, which has been under the control of Syrian rebels since January.

The Local Coordination Committees activist network and the Britain-based Syrian Observatory for human rights say Rastan was under renewed and intense shelling as of Friday morning.

Videos posted online by activists showed thick smoke and shells slamming into districts in Rastan.