Egyptian police arrested seven people on Monday after they were seen raising a rainbow flag at a concert, security sources said, in a rare public show of support for lesbian, gay, bisexual and transgender rights in the conservative Muslim country.

Security sources said the seven were arrested for “promoting sexual deviancy,” a euphemism in Egypt for homosexuality, after they were seen on camera raising the rainbow flag at a Mashrou’ Leila concert, a popular Lebanese alternative rock band whose lead singer is openly gay.

Egyptian Public Prosecutor Nabil Sadek ordered the State Security Prosecution to immediately investigate the incident, state news agency MENA reported. Read more via Reuters