Sporadic explosions and gunfire have been heard in the Yemeni capital Sanaa hours after the government announced a ceasefire with a breakaway general and armed opposition tribes.

On Tuesday evening, residents of the Hasaba and Sofan neighborhoods reported that they could still hear fighting nearby after the 3pm ceasefire deadline earlier announced by state television.

Tribal sources told the AFP news agency that at least one man was killed and nine people were wounded when shelling struck Hasaba. Fighting also continued in Taiz, Yemen's second-largest city, where 15 people were killed, the AFP reported.

According to the earlier government announcement, embattled President Ali Abdullah Saleh had reached a ceasefire agreement with dissident General Ali Mohsen al-Ahmar. The two sides' forces have been engaged in bloody battles for weeks, and the violence escalated in recent days.

After the fighting seemed to continue on Tuesday, state television said that the truce was "stabilizing" and that a mediation committee set up to negotiate the ceasefire was still "making contact with all parties".

Saleh, who has ruled for 33 years, also summoned the ambassador from the United States to say that he is prepared to sign a deal that will see him step down, a promise he has made several times before.

'Listen to your people'

"The people want to prosecute the butcher," the Associated Press news agency quoted the protesters as chanting. They were demanding a trial for Saleh.

Some also held up posters saying that after the death of Libya's Muammar Gaddafi, it was time for Saleh to "listen to your people".

Amid the shooting, the marchers were forced to retreat from the surrounding streets towards Change Square, AP said.

Saleh's forces in Sanaa have exchanged gunfire with army units who defected to the opposition early on in the uprising and whose forces now escort and protect the protesters.

Mohammed al-Qubati, who runs a field hospital at the protesters' camp site, said at least 40 people were wounded by Saleh's forces during Tuesday's shooting.

He said dozens also suffered breathing difficulties because of tear gas fired by the troops and several passed out.

Violence in Sanaa has escalated in the wake of a non-binding UN Security Council resolution urging Saleh to sign a Gulf states-brokered deal that paves the way for his resignation.

Saleh welcomed the resolution on Monday, but has so far refused to sign the agreement, despite increased regional and international pressure to do so.

Meanwhile, in Yemen's second largest city Taiz, seven civilians died and at least 30 others were wounded in shelling and in clashes between armed tribesmen who back the anti-government protesters and pro-Saleh troops, medics and sources told Al Jazeera.

Witnesses there described scenes of fear and chaos as mortar shells fell randomly on city neighborhoods overnight and early on Tuesday, damaging dozens of houses and forcing schools to shut down.

PHOTO CAPTION

Defected army soldiers ride a military vehicle during a rally to demand the ouster of Yemen s President Ali Abdullah Saleh in Sanaa October 21 2011

Al Jazeera