Women's groups, claiming a rec-ord turnout at a pro-abortion rally, vowed to use the show of strength as a political weapon against legislators who would take away a woman's right to choose.

Rally organizers, emboldened by the sight of marchers crowding the mile-long route from the Washington Monument to the Capitol on Sunday, threatened to hound out of office lawmakers oppose to the principle of legal abortions."The government will ignore this show of force at its peril," an organizer told reporters.

President Bush in January addressed a rally of about 45,000 anti-abortion activists and decried the "American tragedy of abortion on demand."

The right to abortions, established by the landmark 1973 Roe vs. Wade case, is under attack as the Supreme Court prepares to vote on a case that could return to individual states the right to limit abortions.

The National Organization for Women, which organized the event, said it had collected 600,000 signatures from rally participants. Washington Park Police said the crowd was about half that, but the crowd still matched the biggest civil rights and anti-Vietnam war marches of the past.

"This is the biggest march for women in the history of the nation," said NOW president Molly Yard.

Protesters of all generations turned out for the demonstration, with some bringing their children.

On April 25 the Supreme Court will begin deliberations on the case of Webster vs. Reproductive Health Services which has challenged the constitutionality of a Missouri law barring abortions after 20 weeks of pregnancy.

Anti-abortionists staged counter protests along the route - some kneeling in silent prayer, others calling marchers "murderers" and "prostitutes."

The U.S. annual abortion rate of 28 per 1000 women in the child-bearing years, 15 to 44, puts it among the highest of Western industrialized countries.

In Florida, an abortion clinic in Ocala, Fla., was destroyed by an arson fire, and another in Fort Myers was damaged Sunday by a blaze of suspicious origin.