An 18-year-old man was found guilty of attempted murder on Friday in connection with the explosion that took place on a London underground train on September 15, 2017, Reuters reported on Friday. Ahmed Hassan was arrested in Dover a day after the explosion at the Parsons Green station in West London that injured 30 commuters.

The Iraqi teenager is believed to have earlier showed warning signs to authorities that he could carry out a terror attack, BBC reported. He was also referred to the government’s deradicalisation programme before the attack took place.

The judge said the teenager was convicted based on overwhelming evidence. The jury at the court took just a day to find him guilty.

Hassan had arrived in the United Kingdom as a child asylum seeker. He had claimed to have been groomed by the Islamic State group. The accused told the court that he made the bomb since he was bored and depressed, and wanted to draw attention to himself, The Guardian reported.

The improvised explosive device went off at Parsons Green station, but it did not fully explode. The attack was the fifth major one in 2017 in the United Kingdom.