Washington - The Senate on Wednesday broke through the usual partisan gridlock to swiftly approve legislation aimed at reducing veterans' long waits for health care, as the FBI announced that it has launched a criminal probe in the Department of Veterans Affairs scandal.

The bill would allow veterans facing long waits at VA facilities to seek care from private doctors, expand the VA secretary's authority to fire staff for poor performance, authorize the department to lease 26 new health facilities in 17 states and Puerto Rico. It also would provide $500 million for expedited hiring of new VA doctors and nurses.

The 101-page compromise Veterans' Access to Care through Choice, Accountability and Transparency Act was written and approved with unusual speed, a reflection of the political importance to both parties of the nearly 6.5 million veterans who use VA's 1,700 hospitals and clinics.

"There are serious problems at the VA now, and they must be addressed now," Sen. Bernie Sanders, I-Vt., chairman of the Senate Veterans' Affairs Committee, told colleagues.

"There's no way we can compensate for those who have gone without the treatment that they've earned," added Sen. John McCain, R-Ariz., who developed the compromise legislation with Sanders. "But at least we can expeditiously fix this problem to the best of our ability."

McCain called the legislation a beginning to "fix this gaping wound in America's conscience."

The measure's passage came as FBI Director James Comey told the House Judiciary Committee that the FBI has begun a criminal probe of the VA scandal, led out of the Phoenix field office where the allegations first surfaced.

"We'll follow it wherever the facts take us," Comey said, declining to discuss it further.

The VA inspector general has been working with the Justice Department, but lawmakers from both parties have pressed for the FBI to play a bigger role in the investigation.

The Senate bill must be reconciled with House VA reform legislation. But the bills include a number of similarities, including allowing veterans who are unable to receive an appointment at a VA facility within the department's wait-time goals or living 40 miles from a VA facility to seek private care.

But there are a few differences that could prove tricky during House-Senate negotiations on a final bill.

A House bill approved Tuesday would eliminate VA bonuses for fiscal 2014 through 2016, while the Senate bill would eliminate the use of waiting times for determining employee bonuses.

The Senate bill, like a House-approved measure, would expand the VA secretary's authority to fire or demote senior staff for poor performance. But the Senate bill includes due-process protections for employees to prevent what Sanders called the "politicization of the VA."

The Senate bill also would extend college education benefits to spouses of service members killed in the line of duty, guarantee in-state tuition for veterans at public colleges and universities and improve access to health care for military sexual assault victims.