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By Jessica Donati and Hamid Shalizi

KABUL, March 20 (Reuters) - Gunmen fired shots inside a luxury hotel on Thursday in the centre of the Afghan capital Kabul, police said, but the scale of the attack and the number of casualties was unclear.

Security sources told Reuters that two or three gunmen armed with pistols entered the Serena hotel by a back door. Two people had been wounded, they said. There were no details on the nationality of those hurt.

One person who was taken to safety along with other guests said that the shooting appeared to begin in the hotel restaurant.

Another guest, hiding in his room, said he could hear sporadic gunfire.

Police spokesman Hashmatullah Stanekzai confirmed that shots had been fired, but said it was unclear if it was an attack by insurgents. He did not speculate on other possible attackers.

Spokesmen for both the Interior Ministry and the Taliban said they were seeking more information about the incident.

The hotel was attacked in 2008 by a suicide bomber and six people were killed.

Since then, it has beefed up its protection and is considered the safest place to stay in Kabul, protected by multiple layers of security including metal detectors and armed guards. It is home to many United Nations staff and foreign delegations.

Earlier in the day, the Taliban attacked a police station in the southern city of Jalalabad with multiple suicide bombers and gunmen. At least 11 people were killed.

The Taliban have vowed to kill anyone associated with next month's presidential elections. The April 5 polls should mark the first time one elected government hands power to another in the history of Afghanistan. (Reporting by Katharine Houreld, Editing by Maria Golovnina and Mark Trevelyan)

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