Fed-up lawmakers on a House of Representatives oversight committee said Tuesday they want to strip a federal nuclear agency of its security responsibilities and threatened to shut down Los Alamos National Laboratory to correct a decade of security lapses there.

Rep. John Dingell, a Democrat, said he has sat through nearly a decade of hearings in which the Energy Department and the nuclear weapons lab where the atomic bomb was developed have promised to fix security problems.

"I've been hearing these promises for a long time, and they've become somewhat tedious," he said.

The lawmakers blistered the lab for its most recent security breach in which a contract worker walked out with hundreds of pages of classified documents. The documents turned up during a drug raid last October involving a man who rented a room at the worker's home.

Rep. Joe Barton, a Republican, said that if problems cannot be solved this time he will ask that Los Alamos lab, in the western state of New Mexico, be shut down.

"There is an absolute inability and unwillingness to address the most routine security issues at this laboratory," Barton said.

Barton, Dingell and others on the House Energy and Commerce Committee introduced a measure Tuesday to strip the National Nuclear Security Administration of its primary security responsibilities and turn them back to the Energy Department because of concerns that NNSA has not fixed security problems at Los Alamos despite tens of millions of dollars spent on improvements.

"NNSA was a management experiment gone wrong," Barton said.

A new management team was installed at Los Alamos less than a year ago, in part to reverse years of security and safety problems.

The embarrassing October incident involving the classified documents resulted in a shake-up in the agency that oversees the lab. Linton Brooks, already reprimanded for an earlier incident, resigned earlier this month as head of the NNSA.