SAN'A, Yemen -- A Yemeni man shot four oil company co-workers Tuesday -- killing an American, a Canadian and a Yemeni -- before shooting himself dead, the Interior Ministry said.
A second Canadian was wounded. The assailant may have suffered from depression, and witnesses reported that during the attack he yelled he was taking revenge "against those who were filing reports about him," a ministry statement said.
The attack occurred in an oil field in the oil-rich northern province of Marib, about 100 miles northeast of the Yemeni capital San'a, a ministry statement said.
A statement by Hunt Oil Co., which supervises the oil rig, said the four victims worked at a rig owned and operated by Nabors Drilling Co. and were shot while working in the field.
The American victim was a Hunt Oil Co. superintendent, while the two Canadians and the Yemeni man, in addition to the alleged killer, were Nabors employees, the Hunt statement said.
The names of the American and Canadians were not released, pending notification of next of kin. The dead Yemeni oil worker was identified as Nazem al-Kabati.
In a statement, the U.S. Embassy in San'a condemned the violence and called on the Yemeni government to investigate. It said American law enforcement personnel would help.
The Yemeni Interior Ministry statement, quoting an unidentified official, said the alleged assailant, identified as Naji Abdullah al-Kumaim, worked for Nabors for seven years and suffered from depression.
"According to testimony from his co-workers, the assailant was suffering from bouts of depression," the statement said. "He was not known to have any previous political affiliations and the motives of the crime are believed to be criminal and personal ... since he was shouting during the shooting that he would take revenge against those who were filing reports about him."
Hunt spokesman Jim Oberwetter, speaking from Dallas, said the company "has suspended our drilling operations in Yemen for the foreseeable future."
He said the company expressed its "heartfelt sympathies to all the victims and their families."
Nabors officials did not immediately return a phone message Tuesday.
Gun violence is not unusual in the largely lawless tribal areas of Yemen, but the country also has been the scene of several Islamic militant terror attacks on Western targets in recent years.
Yves Duval, press officer at the Canadian Embassy in Riyadh, Saudi Arabia, which oversees Canadian interests in Yemen, confirmed that one Canadian was killed and another wounded in the shooting.
"We received a police report confirming that two of our citizens were shot. One was killed and another wounded," Duval told The Associated Press.
The wounded Canadian was evacuated by plane to a hospital in San'a, Duval said. He did not disclose the extent of the victim's injuries.
Canada does not maintain an embassy in Yemen.
In Ottawa, Canadian Foreign Affairs spokesman Reynald Doiron, said, "It might have been something of a personal nature between the aggressor, who killed himself afterward, and the American citizen."
Yemen long has been a hotbed for terrorists and is the ancestral homeland of al-Qaida leader Osama bin Laden.
In 2000, an explosives-laden boat rammed the American destroyer USS Cole off Yemen, killing 17 U.S. sailors. On Dec. 30, 2002, a suspected Islamic militant shot dead three U.S. Christian missionaries who worked at a Baptist-run hospital.