Zamboanga City (CNN Philippines) — Local authorities arrested three suspected members of the Abu Sayyaf group who were allegedly planning an attack during the Zamboanga Hermosa Festival, police said Monday.

Police confiscated grenades, a .45-caliber pistol, a detonating cord, and a blasting cap from the suspects.

Police said the suspects plotted to hurl a hand grenade at RT Lim Boulevard, one of the popular sites in this year's festivities, which happens October 1-12.

The suspects were also planning to kidnap a prominent businessman in Zamboanga City, police said.

Zamboanga Police Office Spokesperson Chief Inspector Helen Galvez identified the suspects as Abde dela Cruz (aka Sherwin), Jabar Ignohasim, and Abdulla Yusup -- all residents of Jolo, Sulu.

They are believed to be members of the Sulu-based subgroup of the Abu Sayyaf under the leadership of Alhabsi Misaya, according to police intelligence officers.

Related: Who are the Abu Sayyaf?

Zamboanga police officers were about to serve a warrant of arrest against Dela Cruz at a pension house in Zamboanga City when he and two other suspects tried to escape.

The police nabbed the suspects at 2:45 p.m. on Monday.

According to police, the three suspects arrived via a passenger vessel from Jolo Monday morning and checked in at a local pension house.

CNN Philippines' Digital Producer Eimor P. Santos contributed to this report.