Tens of thousands of ultra-Orthodox Israelis held a mass rally in Jerusalem, shutting schools, roads and trains, in protest against attempts to end their exemption from military service, an issue threatening the government of Prime Minister Benjamin Netanyahu.

The demonstrators are mostly the backers of two ultra-Orthodox, or Haredi, parties that joined Netanyahu’s ruling coalition nearly three years ago. Their decision to quit over the issue in July and boycott legislative votes has paralyzed the government, and they’ve vowed to bring it down if their men are ultimately drafted.