Fierce clashes broke out between Syrian troops and rebels yesterday as the regime sent reinforcements into a number of hotspots despite President Bashar al-Assad's pledge to implement a peace plan.

The Syrian Observatory for Human Rights said fighting gripped several parts of the country including the southern province of Daraa, northwest Idlib province, Homs in central Syria and near the capital.

At least 18 civilians were killed in the fighting along with seven soldiers and four rebels, the Britain-based group said.

The latest unrest came as Red Cross chief Jakob Kellenberger was on a fresh mission to Syria — his third since last year when Damascus launched a crackdown on antigovernment protests that the UN says has left more than 9,000 dead.

UN-Arab League envoy Kofi Annan on Monday said Assad had accepted an April 10 deadline to start implementing a peace plan.

Annan told the UN Security Council that

Assad had agreed to "immediately" start pulling troops out of protest cities and complete a troop and heavy weapon withdrawal by April 10.

But Amnesty International cast doubt on the Syrian regime's commitment to stop the bloodshed, saying that arrests were continuing despite the pledge made to Annan.

"Arrests have been continuing in Syria only days after the Syrian government agreed to implement parts of Kofi Annan's six-point plan," the rights group said in a statement.

"There are thousands of people still in detention across Syria, many held incommunicado, in danger of being tortured, and without access to lawyers," said Ann Harrison, Amnesty International's Middle East and North Africa deputy head.

"Continuing to hold people in such conditions, and making new arrests like this, raises serious questions about how serious the government is about respecting its commitments under the Annan plan."