The Indian Navy issued its highest alert for Mumbai on Thursday after two school students claimed to have seen armed masked men near a naval base in Uran, The Indian Express reported. The Indian Navy, Mumbai’s anti-terror squad and other security agencies have been directed to heighten security, while the city police imposed nakabandis (road blocks).

The children reportedly saw around five men dressed in black "pathan clothes and speaking a different language" in Uran, which is almost 50 kilometers from Mumbai, NDTV reported. Officials said the children heard the men mention the words "ONGC" and "school".

Uran Education Society School, the school the students belong to, has declared a holiday on Friday for security reasons. KP Bakshi, Assistant Commissioner of Police (Home), has asked Deputy General of the state police force to submit a detailed report on terror alert by Friday.

Indian security forces have been on a high alert since the attack on an army installation in Uri, Jammu and Kashmir on Sunday. An official said, "We cannot overlook anything at this point." Around 166 people lost their lives in a terror attack in Mumbai in 2008.