AMSTERDAM, May 8 — Pro-Palestinian protesters built barricades at the University of Amsterdam today, using desks and railings to block off the canalside entrance in the heart of the city as they vowed to stay put until the institution severs all ties with Israel.

Riot police used a bulldozer to knock down barricades at another UvA site on Tuesday and detained 169 people, but said the university had not yet asked for similar intervention today.