Indian IT giants TCS, Infosys and Wipro today said their employees in tsunami-hit Japan are safe and are constantly monitoring the situation there.

"All our employees are safe. Since our centre in Yokohama is quite far from the epicentre, there wasn't much impact.

However, our HR teams are constantly monitoring the situation and we will take actions as required," a TCS spokesperson told PTI.

A massive earthquake hit Japan followed by a devastating tsunami on March 11, leaving thousands of people dead or unaccounted for, as houses were swept away, ships were overturned, vehicles and several buildings, including a petrochemical plant, were set on fire.

The country is now facing a radiation scare with a hydrogen explosion occurring today at the quake-hit Fukushima nuclear plant's second reactor, leaving three workers injured and seven missing. This is the second reactor of the plant that has witnessed an explosion.

TCS has over 200 people in Japan, while its peers Infosys and Wipro have over 250 people and 400 employees,respectively.

"Infosys has an office in Tokyo and has several employees in Fukuoka and Nagoya cities. Our local teams in these cities are making arrangements to support our employees' requirements at this time," Infosys spokesperson said.

According to the software industry body Nasscom, Japan accounts for about two per cent of the IT-BPO industry revenues.

Wipro, in a statement said, "All our employees are safe.

Necessary emergency procedures have been activated and we are continuing to monitor the situation."

India's External Affairs Minister S M Krishna has also said all Indians in Japan are safe.

"All of them (Indians in Japan) have established communication with our embassy. And all of them are safe," Krishna said.