Russia Says Syrian Regime Forces Targeted by US-Led Coalition Airstrikes

The US says it has halted airstrikes afters possibly hitting Syrian regime.

— -- The U.S. military says it has halted airstrikes over Syria after the Russian Defense Ministry accused the U.S.-led coalition of carrying out a strike that hit Syrian government soldiers, killing 62 and injuring 100.

U.S. Central Command acknowledged the accusations in a statement it released this afternoon, but did not squarely claim responsibility for the reported deaths and injuries.

A senior Obama administration official told ABC News that the U.S. had "relayed our regret" to the Syrian government through Russian officials.

"The United States has relayed our regret through the Russian Federation for the unintentional loss of life of Syrian forces fighting ISIL," the official said. "The U.S. will continue to pursue compliance with the Cessation of Hostilities as we continue military action against ISIL and Al Qaida."

A senior defense official told ABC News the target was a collection of vehicles and personnel that had been tracked by intelligence for a couple of days and were believed to be ISIS. The group of vehicles included at least one tank. Only one strike of a planned series of strikes occurred before the coalition was called off by the Russians, this official said. That initial air strike destroyed half a dozen vehicles and personnel, according to the official.

"If this airstrike was caused by target location error, then this is a direct consequence of the U.S. side's stubborn reluctance to coordinate with Russia its actions against the terrorist groups operating in Syria," Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov said today.

U.S. Central command denied that claim, saying it voluntarily warned the Russians ahead of time about the impending airstrike.

"Coalition members in the Combined Air Operations Center had earlier informed Russian counterparts of the upcoming strike," Central Command said in its statement. "It is not uncommon for the Coalition Air Operations Center to confer with Russian officials as a professional courtesy and to deconflict Coalition and Russian aircraft, although such contact is not required by the current U.S.–Russia Memorandum of Understanding on safety of flight."

Nevertheless, the Russians are claiming their Syrian allies have been killed by the U.S. military, just as the U.S. and Russia are trying to maintain the fragile, nationwide cease-fire that went into effect Monday.

That cease-fire calls on the Syrian regime to cease all airstrikes over U.S.-backed opposition forces and limits it to striking ISIS targets. It also calls for increased military cooperation between the U.S. and Russia after a seven-day period of calm and the sufficient delivery of humanitarian aid. Six days since the start of the cease-fire no aid has been delivered.

The U.S. military said in its statement that it has previously targeted ISIS in the same area where the Syrian regime forces were reportedly killed today.

"Syria is a complex situation with various military forces and militias in close proximity, but coalition forces would not intentionally strike a known Syrian military unit," the statement read. "The coalition will review this strike and the circumstances surrounding it to see if any lessons can be learned."

The Associated Press contributed to this report.