Video footage of Friday’s attack on former Prime Minister Shinzo Abe has been shown repeatedly on TV and shared via social media — and it may be having a negative effect on the well-being of those who watched it.

Some viewers may report symptoms of acute stress including insomnia and nightmares after viewing the images of the attack, mental health experts say, urging these people to stop watching and consult a medical specialist if necessary.

Pictures and video clips of Friday’s incident — where Abe is seen being gunned down while making a speech on the street in Nara — could be particularly harmful to children, people with psychological issues and survivors of post-traumatic stress disorder, said Hirokazu Tachikawa, a professor of disaster psychiatry at the University of Tsukuba.