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Gunmen ram van into Microsoft's Greek headquarters in Athens, set vehicle on fire

John Kolesidis / Reuters

A security guard talks on the telephone after an attack on Microsoft's Greek headquarters in the north of Athens on Wednesday.

ATHENS - Gunmen rammed a van packed with gas canisters into Microsoft's Greek headquarters in Athens and then set the vehicle on fire, causing damage but no injuries, police said on Wednesday.

At least two people wielding pistols and a machine gun kept security guards away as they carried out the attack at about 3:45 a.m. local time on Wednesday (9:45 p.m. ET Tuesday), police said.

There was no immediate claim of responsibility. Authorities said no warning call had been made before the incident.

Arson attacks against banks, foreign firms and local politicians have become more frequent in Greece in recent years as the country battles soaring unemployment and struggles through a recession deepened by austerity policies imposed by foreign lenders.

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The attacks usually occur late at night and rarely cause injuries.

Previous assaults have been mostly blamed on left-wing extremist groups, but police said it was too early to say who was behind Wednesday's attack.

$75,000 in damage
The van, which contained three inflammable gas canisters and five cans of gasoline, was completely destroyed while the ground floor of the U.S. software firm's office suffered heavy damage, police said.

Greece appeared to have avoided crashing out of the euro currency zone early Monday after political parties in favor of an international bailout deal won a slim election majority – but the region's debt crisis showed no sign of abating. NBC's Stephanie Gosk reports.

Police said initial information indicated three people had been inside the van. They forced the two security guards at the building to leave before they reversed the van into the front entrance, smashing the door.

The two security guards were giving testimony to police.

Microsoft said it would shut its office in the city while it assessed the damage.

"Staff were told not to come to work today, and probably also tomorrow," the company's spokeswoman Lia Komninou said on Skai TV.

The fire brigade estimated the damage at about 60,000 euros ($75,000).

In February, a small bomb was left on an empty subway train in Athens. A far-left group fighting the austerity policies later claimed responsibility.

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Growing public anger at the impact of the austerity measures was reflected in two parliamentary elections in May and June, in which parties opposed to the terms of the country's international bailout performed strongly.

Editor's note: Msnbc.com is a join venture between Microsoft and NBC Universal.

Reuters and The Associated Press contributed to this report.

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