BOSTON — Demonstrators seeking a cease-fire in Gaza blocked traffic on the Boston University bridge during rush hour Thursday, slowing traffic to a trickle.

The group chanted “Cease-fire now!” during the protest amid an Israeli ground offensive in Gaza that followed Hamas-led attacks in Israel on Oct. 7. They also held signs that said, “Let Gaza Live.” The bridge connects Boston and Cambridge.

Activists were demanding that Democratic Sen. Elizabeth Warren of Massachusetts support an immediate cease-fire and use her influence to stop the Israeli government’s military action.

Boston Police were at the scene of the protest, which was organized by IfNotNow, which said it represented members of Jewish community in Boston.

The protest came as Israeli forces dropped leaflets warning Palestinians to flee parts of southern Gaza, residents said Thursday, signaling a possible expansion of their offensive.