NEW YORK — The NFL announced Sunday it is investigating a rash of positive COVID-19 test results that all came from a lab in New Jersey as training camps push toward the opener less than three weeks away.

“​Saturday’s daily COVID testing returned several positives tests from each of the clubs serviced by the same laboratory in New Jersey,” the NFL said in a statement. “We are working with our testing partner, BioReference, to investigate these results, while the clubs work to confirm or rule out the positive tests. Clubs are taking immediate precautionary measures as outlined in the NFL-NFLPA’s health and safety protocols to include contact tracing, isolation of individuals and temporarily adjusting the schedule, where appropriate. The other laboratories used for NFL testing have not had similar results.”

Bills GM Brandon Beane said he thought there were 10 or 11 teams affected by the irregularities.

Among teams reporting false positives, the Minnesota Vikings said they had 12, the New York Jets 10 and the Chicago Bears nine.

The Jets canceled a walk-through on Saturday night but had a full practice Sunday morning after the previously positive tests came back negative. The Bears moved their practice scheduled for Sunday morning to the afternoon.

The Pittsburgh Steelers said they had six false positives and those players will be back at practice Monday. The Philadelphia Eagles held out four players from working out Sunday. The Cleveland Browns initially canceled their practice, but after re-testing turned up negative tests they decided to have their workout.

The number of positive COVID-19 tests from a specific facility that might actually be false demonstrates the precarious position the NFL is in less than three weeks from the regular-season opener.

“Definitely probably better that this happened now than three weeks from now,” said Beane, whose club had some of those positive results. “But it seems like every few weeks, or even every week, something’s going on. Who know what the next curveball will be?”

Beane said tests in the Northeast had gone “haywire,” and called it “a lab issue and not a true issue with our guys currently” after several Bills were held out of practice.

Anyone testing positive for COVID-19 – even a false positive upon a retest – is required to have two more negative tests before being cleared to return.

Heading into this weekend, there had been four confirmed positive tests for players who were at training camps.

RAVENS: The Baltimore Ravens terminated the contract of seven-time Pro Bowl safety Earl Thomas, who got involved in a fight with a teammate Friday and did not attend practice Saturday.

According to a statement by the team, Thomas was released “for personal conduct that adversely affected the Baltimore Ravens.”

The action stems from Thomas’ fray with defensive back Chuck Clark at practice after Thomas admittedly blew a coverage assignment. Although the Ravens don’t have someone else with his talent at free safety, keeping Thomas would have created the potential for poor chemistry on a team with aspirations of playing in the Super Bowl.

BROWNS: Thin and inexperienced at linebacker, the Cleveland Browns signed former Super Bowl MVP Malcolm Smith.

Smith helped lead the Seattle Seahawks to an NFL title after the 2013 season, when he returned an interception for a touchdown, recovered a fumble and had 10 tackles in a 43-8 blowout of Denver.

49ERS: The San Francisco 49ers had two key players leave practice early Sunday with rookie receiver Brandon Aiyuk and edge rusher Dee Ford each suffering lower-body injuries.

There was no immediate word on the extent of the injuries.

CARDINALS: The Arizona Cardinals signed veteran cornerback Dre Kirkpatrick to boost their secondary after a season-ending injury to Robert Alford.of the Jets’ top special teams performers. He injured an ankle in the offseason, but appeared to move well during drills Sunday.

WASHINGTON: The team released Cody Latimer amid his legal issues before he practiced a single snap with the team.

The veteran wide receiver signed a contract with Washington during the offseason. He was arrested in May and charged with a felony count of illegal discharge of a firearm.

LIONS: The Detroit Lions signed defensive end Will Clarke, adding much-needed depth at the position.

Clarke, who has seven career sacks in 53 NFL games, joined the team for practice on Sunday. The Lions released guard Caleb Benenoch to clear a spot on the roster for Clarke.