Tehran: A 4.3-magnitude earthquake struck Iran's Gerash region on Tuesday, amid the escalating conflict in the Islamic Republic.  

There were no immediate indications of major damage or injuries.

The quake intensified the existing regional tensions. 

Iran's Islamic Revolutionary Guard Corps (IRGC) released figures on US casualties during the first two days of what it described as retaliatory strikes, with the numbers differing significantly from those announced by the United States, reported local media on Tuesday.

An IRGC spokesperson said up to 650 US soldiers were killed or wounded during the first two days of the retaliation. 

The spokesperson said IRGC missiles and drones struck the headquarters of the US Navy's Fifth Fleet in Bahrain multiple times, and that attacks on US military bases in Bahrain resulted in 160 US casualties.

The US military said that as of 4 p.m. Monday (2100 GMT), six US service members had been killed in military operations against Iran. US media reported that 18 additional troops were seriously wounded. US officials said there have been no fatalities at US military bases in Bahrain.

The IRGC spokesperson also said a US combat support ship was heavily damaged by IRGC missiles, reiterating that four cruise missiles were fired at the USS Abraham Lincoln aircraft carrier, which then "fled" southeast toward the Indian Ocean, reports Xinhua news agency.

Earlier, US Central Command formally denied claims from the IRGC that they had struck the USS Abraham Lincoln with missiles, labelling the Iranian assertions as "disinformation" and a "lie," adding that the missiles launched by Iran "didn't even come close."

The claims by both sides could not be independently verified.