The U.S. government decided to tighten visa rules for foreign students after the Boston marathon bombings.

The move came in response to charges brought against arrested student from Kazakhstan Azamat Tazhayakov whose visa was invalid at the moment he arrived in the country, BBC reported.

The investigators said Tazhayakov tried to remove backpack from Dzhokhar Tsarnaev’s room. In January Tazhayakov arrived in New York when his visa was terminated after his academic dismissal from the University of Massachusetts-Dartmout.

Internal ministry will immediately start to check the visa status of every student.