Published: Dec 29, 2011 6:00 PM EST

MOGADISHU, Somalia (AP) - A disgruntled former employee shot at least two international workers from the aid group Doctors Without Borders at the group's office in the Somali capital, a security guard said Thursday. At least one person was killed.
    
Ahmed Ali, a security guard for the aid group which is known as MSF - its initials in French - said a Somali employee who ran its logistics was dismissed from his job on Wednesday. He returned on Thursday and opened fire, hitting the two aid workers, killing one of them, Ali said.
    
"We confirm that a serious shooting incident has taken place in the MSF compound in Mogadishu," said spokeswoman Maimouna Jallow. "At this point we don't have more information about the scale and the extent of the incident. MSF is doing everything it can to ensure the security of its staff."
    
A Nairobi, Kenya-based security official said he believed three international workers had been shot. The security official spoke on condition he not be identified because the information hadn't yet been released publicly.
    
The nationalities of the aid workers weren't immediately known, though Ali and the Nairobi official said the person killed was believed to be French.
    
Mogadishu is one of the most dangerous locations for aid workers to conduct business. Many groups don't allow international workers to stay in the capital for long and rely primarily on Somali employees. International aid workers face potential attacks from militants and kidnappings for ransom.
    
Suspicion following a violent attack like Thursday's often falls on the militant group al-Shabab. But it appeared the insurgents had no hand in the attack, and in fact were the first to report that an attack was under way at the Doctors Without Borders compound, putting out a series of tweets.
    
They said a "fierce battle is now raging" inside the MSF building in Mogadishu. "A gunman has stormed the building & opened fire on MSF staff inside," al-Shabab tweeted in a series of about eight postings on Twitter.
    
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Associated Press writer Katharine Houreld in Nairobi, Kenya contributed to this report.

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