Philippine troops killed two communist insurgents who attacked an aid convoy en route to typhoon-devastated Tacloban on Tuesday, the military said, as soldiers were deployed to quell looting by hungry survivors.

Bodies still littered the streets of the city, where the United Nations fears 10,000 people could have died when the category-five Haiyan struck on Friday.

Thousands of people whose homes were destroyed by one of the most powerful typhoons on record were facing yet another night of misery, many without shelter, as troops established checkpoints to try to restore order and allow much-needed aid to percolate through.

Some of that aid fell victim to one of the Philippines' long-running insurgencies when 15 communist rebels ambushed trucks on their way to the storm-wracked region, a local commander told AFP.

"There were no casualties on the government side," Lieutenant Colonel Joselito Kakilala said, adding that two members of the New People's Army, the militant wing of the Communist Party of the Philippines, were killed and another wounded in the clash in Matnog town, some 240 kilometres (150 miles) from Tacloban.

In the city itself, a curfew was in force as armoured vehicles and elite security forces patrolled streets where famished survivors had raided stores and ransacked other aid convoys.

Hundreds of soldiers and police were in evidence around the city, the capital of the provincial island of Leyte, which bore the brunt of Haiyan, one of the strongest storms on record.

Tacloban -- a city of 220,000 residents -- has been the scene of the worst pillaging. Survivors reported gangs stealing consumer goods including televisions and washing machines from small businesses.

As night fell in the ravaged city, heavily armed policemen manned checkpoints or patrolled the corpse-lined streets, on the prowl for looters.

Manila police officer Julian Bagawayan said 150 members of his riot police squad were flown to Tacloban to enforce a nighttime curfew that began Monday.

"Our mission is to help the police of Tacloban because they are also victims. We all know the government is down. We came here to help the government," he said, his assault rifle in his hand.

"We are here to stop people looting properties and breaking into homes."

Earlier Tuesday, Interior Secretary Mar Roxas said four Simba armoured personnel carriers had been dispatched to Tacloban.

"We are circulating them in the city to show the people, especially those with bad intentions, that the authorities have returned," Roxas told DZMM radio, adding checkpoints were being used to prevent people mobbing relief trucks.

Super Typhoon Haiyan flattened buildings and knocked out electricity and water supplies as tsunami-like waves and brutal winds tore across large swathes of the of the archipelago, leaving desperate survivors with virtually nothing.

Some have resorted to theft, with a charity saying that in one case a man with a machete tried to rob aid workers who were receiving a delivery of medicine.

"The presence of policemen, military and government forces will definitely improve things (but) it will not be overnight," Roxas said, confirming reports that the Tacloban city government had imposed a curfew from 10:00 pm (1400 GMT) to 6:00 am.

"It is a tool that we are using to minimise the looting and break-ins. We know some people cannot return home (during curfew) because their homes were washed away, but it is more effective against roving gangs who are looking for targets of opportunity," he said.

It is not clear where newly homeless residents are meant to go during this period.

AFP journalists in Tacloban described the city as a "ghost town", with bodies still lying on the streets four days after the typhoon hit and those shops that were not destroyed boarded up.

Piles of debris, including wrecked homes and toppled trees, meant little food and medicine got through to survivors in the early days.

"That is why they were desperate and hungry", hotel owner Kenneth Uy said, describing the immediate aftermath of the storm as "a descent into chaos".

Police have said that some local councillors led the looting of shops to provide food to constituents.

Roxas added that the public works department had cleared at least one lane of a highway entering the city, which would speed up entry of supplies.

He said the government's three main priorities were to restore peace and order, bring in relief goods and start collecting dead bodies.

"Now that we have achieved number one and two, the priority is the recovery of the cadavers," he said.