US auto safety regulators are probing two recent recalls by Ford Motor Co. as the carmaker struggles to contain quality lapses in its vehicles.

The National Highway Traffic Safety Administration said on Monday it has opened two new investigations into Ford recalls, the latest scrutiny by U.S. regulators of the No. 2 U.S. automaker. Last week,

NHTSA unveils two investigations into recalls that may not have worked, just days after announcing civil fine against Ford for moving too slowly.

The federal government says it has launched two investigations into Ford's recall practices after some were not comprehensive enough and others may not have worked to solve the problem.

The National Highway Traffic Safety Administration said on Monday it has opened two new investigations into Ford recalls, the latest scrutiny by regulators of the No. 2 US automaker. Last week, Ford agreed to a $165 million civil penalty after an NHTSA investigation found the automaker failed to recall vehicles with defective rearview cameras in a timely manner.