Gen. David Petraeus, the top U.S. commander in Iraq, says 13 Americans were electrocuted in Iraq since September 2003 and a contractor has been ordered to inspect the facilities it maintains there for electrical safety hazards, a Pennsylvania senator said.

The military had acknowledged that 12 Americans died in Iraq from accidental electrocution. Sen. Bob Casey said he learned last week from Petraeus that 10 soldiers, one Marine and two private contractors died. Casey said he was not given details on the 13th fatality.

"At least one death is on the record that wasn't on the record before," Casey told The Associated Press on Monday. "It's also very troubling that it takes this long to get this type of information from the Department of Defense."

Petraeus submitted his comments in writing last week to Casey because the Democratic senator's allotted time to question Petraeus before the Senate Foreign Relations Committee in April had elapsed.

Two electrocutions occurred at different housing facilities and involved soldiers taking showers, Petraeus told Casey.

One of the soldiers killed was Staff Sgt. Ryan Maseth, 24, of Pittsburgh, who died Jan. 2 in his barracks in Baghdad. An Army criminal probe blamed improper grounding of an electric pump that supplied water to the building.

Maseth's family has sued KBR Inc., the Houston-based contractor responsible for maintaining Maseth's barracks.

Petraeus said KBR received $3.2 million for maintenance services as part of a February 2007 contract modification. According to Petraeus, KBR had previously provided "only limited technical inspections" at Maseth's barracks.

Inspections performed Feb. 10, 2007, "revealed no deficiencies related to the water pump contributing to Maseth's death but did indicate other grounding issues," Petraeus said.

Casey said he was told the Pentagon has directed KBR to inspect all maintained facilities in Iraq where no prior inspection was performed and to "perform life, health and safety operations" on all other maintained buildings and make needed repairs.

"It's especially troubling that a contract modification didn't prevent (Maseth's death) from happening," Casey said. "Taking a shower should not be an act for which you risk your life."

In a statement Monday, KBR said it is fully cooperating with the government and has "found no evidence of a link between the work it has been tasked to perform and the reported electrical safety issues."

The Department of Defense Inspector General is investigating the deaths, as is the House Committee on Oversight and Government Reform. Casey also wrote to Defense Secretary Robert Gates this month seeking specifics on base inspections and repairs.