VALLETTA, April 15 (Xinhua) -- Three teenagers, thought to be the ringleaders of the hijacking of an oil tanker off the Libyan coast, are set to be indicted for their part in the incident.

A Maltese court of Magistrates ruled on Monday that there are sufficient grounds to indict the three unnamed teenagers who hijacked a tanker which had rescued them at sea.

The three teenagers -- aged 15, 16 and 19 -- are currently facing charges of having unlawfully seized control of the ship, a crime which under Maltese law is punishable by a jail term between 7 and 30 years.

After being rescued at sea together with around 100 others, the migrants are alleged to have threatened the crew and forced it to change course for Malta, once they realized they were going to be returned to Libya.

The migrants are thought to have used tools and heavy metal objects as makeshift weapons to make the crew of the vessel do their bidding. The hijack came to a close when the ship was stormed by Maltese special forces soldiers as it entered Maltese waters.