(Updates death toll, attribution in first paragraph)

CAIRO, Dec 25 (Reuters) - The death toll from the collapse of a 12-storey residential building in Egypt's Mediterranean city of Alexandria rose to 14 on Tuesday after authorities dug more bodies out of the ruins, state news agency MENA said.

Army rescue teams have joined efforts to search for survivors in the rubble, which is thought to have buried 25-30 people.

Rescue workers have extracted at least two survivors from the rubble since the collapse, security sources said. MENA gave the figure as three.

The building disintegrated on Monday as construction workers carried out repairs on the first floor. It was constructed as a seven-storey building in 1982 without a permit, authorities said. The owner obtained a permit later but then illegally added five more storeys.

A source on a panel of experts formed by the government to investigate the collapse said on Monday preliminary findings suggested the causes were shoddy building materials and insufficient use of steel reinforcement bars.

Prosecutors have issued warrants for the arrest of the woman who owned the building, the contractor and the architect responsible for the renovation work that was being carried out immediately before the collapse.

Building collapses are common in Egypt because of lax building standards and poor maintenance.

In a separate incident on Tuesday, also in Alexandria, at least five people were injured when a building partially collapsed, security sources said. (Writing by Aziz El-Kaissouni; Editing by Dominic Evans)

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