Thousands demonstrators rallied Saturday night in Tel Aviv for either compulsory military or national service for all Israelis, DPA reported.
Police spokesman Mickey Rosenfeld told dpa there were 10,000 protestors. Television reports said 15,000 participants.
The rally was headlined "Order 8 - Enough with being suckers" - a reference to Order 8, which the military sends reservists informing them of upcoming reserve duty.
Underlying the protest was the issue of whether ultra-Orthodox Israelis should continue to receive exemptions from the compulsory military service all Israelis must render at age 18, and whether Arab-Israelis, who are not called up for the military, should be compelled instead to do national service.
Many of the demonstrators carried signs, or wore T-shirts, proclaiming, "Service for all."
Vice Prime Minister Shaul Mofaz, who is at loggerheads with Prime Minister Benjamin Netanyahu over the issue, announced Friday that he would attend the rally.
However, organizers did not invite Mofaz or other politicians who showed up to address the crowd.
The debate is the current political hot potato in Israel, and the passions it has evoked have shaken Netanyahu's two-month-old national unity coalition.
The tensions boiled over Monday, when Netanyahu dissolved a committee charged with coming up with a universal draft law to replace one that had effectively exempted ultra-Orthodox seminary students from military service, but which the Supreme Court had struck down in February.
Netanyahu said there had been too many defections from the committee to enable its recommendations to be accepted by parliament. The committee head, Yohanan Plesner of the centrist Kadima Party, Netanyahu's largest coalition partner, published his recommendations anyway.
Although there have also been calls for mandatory national service for Israel's Arab citizens, most of the focus on Plesner's committee concentrated on the issue of ultra-Orthodox enlistment in the military.
His recommendations included drafting ultra-Orthodox men at age 22, allowing 1,500 annual exemptions for outstanding religious scholars and levying fines on those who refuse either to enlist in the military or perform some sort of national service.
Kadima leader Mofaz said he would take his party out the coalition if the recommendations were not adopted.
Ultra-Orthodox politicians have intimated they will quit the coalition if the recommendations are taken on board in full.
But equally, Mofaz cannot afford to anger the ultra-Orthodox parties, whose support he needs to stay in power.
The issue of ultra-Orthodox military service has been simmering in Israel for years.
When the country's first prime minister, David Ben-Gurion, agreed to allow the ultra-Orthodox to evade military service in favour of studying Jewish law, the number receiving such an exemption stood at 400 but by 2010 had swelled to 62,500. According to one set of data, 1,282 out of 8,500 eligible ultra-Orthodox men had enlisted in the military last year.
The law that exempted ultra-Orthodox from compulsory military service was introduced a decade ago. In a 6-3 vote, the Supreme Court declared it unconstitutional, and it will now expire in August. The committee headed by Plesner was charged with devising an alternative.