Tanks mounted with machine-guns have opened fire in the Syrian city of Homs, activists have reported, according to the BBC. It comes a day after authorities in Damascus agreed to an Arab League plan calling on the government to pull the military out of cities. The UK-based Syrian Observatory for Human Rights said the Baba Amr district of Homs came under heavy fire on Thursday. Unconfirmed reports say at least three people were killed in the city. On Wednesday, the Arab League said Syria had agreed to its proposals to end the violence. The plan requires Syria to withdraw all troops from cities and an immediate cessation to all killing. Under the plan Damascus also agreed to stop violence against protesters, release all political prisoners and begin a dialogue with the opposition within two weeks.