Thu Apr 2, 2015 7:59pm EDT

NEW YORK

A Boeing Co (BA.N) procurement official is among seven people who have pleaded guilty in a kickback scheme that involved giving confidential bidding information to suppliers to the aerospace company's satellite division, prosecutors said on Thursday.

The Boeing official, Mark Allen of Boeing's Space and Intelligence Systems unit in El Segundo, California, was charged with conspiracy to receive kickbacks, the prosecutors said.

Allen was charged in April 2013, according to court papers, and pleaded guilty in May 2013. Three others in the alleged scheme - Raymond Joseph, Cesar Soto and Randy Mitchell - also have already pleaded guilty, according to the U.S. Attorney's Office of the United States District Court for the Central District of California.

Their cases were unsealed on Tuesday, and the four are awaiting sentencing, the prosecutors said.

The scheme emerged 10 years after two former senior Boeing executives served prison terms for violating federal conflict of interests rules. The company later tightened its ethics rules and increased internal oversight as part of a $600-million-plus civil settlement with the U.S. Justice Department to resolve the alleged ethics violations and a separate matter in which Boeing allegedly obtained over 40,000 documents from its rival Lockheed in a rocket launch competition.

Boeing said it discovered the scheme involving Allen after receiving a tip from its internal ethics system. It launched an investigation and later alerted U.S. government officials that it suspected an employee was receiving kickbacks.

"Boeing has zero tolerance for such conduct," the company said in a statement.

The government alleges the kickbacks were paid by Alfred Henderson, an executive at A&A Fabrication and Polishing, a Boeing supplier in San Gabriel Valley, California. Henderson pleaded not guilty on Monday and faces a trial in May.

A&A Fabrication has also been charged. The seventh defendant, Noberto Martinez, of Alhambra, California, has signed a plea agreement, the U.S. Attorney's Office said.