Thursday’s strike closed the UN’s 238 schools in Gaza, affecting more than 220,000 students.

It’s the latest flare-up between the United Nations, which runs many Gaza schools and clinics, and the militant group Hamas, which rules the territory.

The UN Relief and Works Agency, which assists Gaza refugees, suspended union chairman Suhail Al-Hindi (SU-hayl Al-HINdi) from his job as a teacher for three months this week, citing unspecified political activities.

Union officials say the strike could be extended to UN clinics if Al-Hindi is not reinstated soon.