VILLIERS-LE-BEL, France, Nov. 27 — Dodging rocks and projectiles, the police lined the streets of this tense suburb Tuesday where angry youths have vowed to seek revenge for the deaths of two teenagers who died in a weekend collision with a police car.

Police union officials warned that the violence was escalating into urban guerrilla warfare, with shotguns aimed at officers — a rare sight in the last major outbreak of suburban unrest, in 2005.

More than 80 have been injured so far — four of them as a result of gunfire — and the rage was still simmering Tuesday afternoon. Inside the city hall of Villiers-le-Bel, a group of visiting mayors appealed for calm while police officers dodged rocks outside.

Image The Louis Jouvet library was torched. Credit... Charles Platiau/Reuters

“We are sitting targets,” said Sophie Bar, a local police officer who stood guard outside. “They were throwing rocks at us and it was impossible to see where they came from. They just came raining over the roof.”