LAGOS (Reuters) – A plot to blow up a major bridge in Nigeria’s commercial capital Lagos has been foiled following the arrest of a 43-year-old man suspected of being part of a gang that planned to carry out the attack, police said.

Nigeria Police Force spokesman Don Awunah said, in a statement issued late on Wednesday, “credible intelligence” suggested the man was an explosives expert who planned to attack the Third Mainland Bridge in the city of 21 million inhabitants.

Awunah said the man told police he was part of a gang with links to the oil-producing Niger Delta that was unhappy because its members were not part of an amnesty scheme for militants in the restive region who laid down their arms in exchange for money and training.

Police were hunting for the rest of the gang, Awunah said.

Boko Haram militants have launched frequent bomb attacks in the northeast in the last few years and other groups have attacked oil facilities in the southern Niger Delta this year but Lagos, in the southwest, is usually peaceful.

The bridge, which carries thousands of drivers each day, spans a lagoon to connect mainland Lagos with the city’s Victoria Island business district where many businesses and banks that drive Africa’s biggest economy have headquarters.

Police said the man from Ondo state, around 250 km (155 miles) from Lagos, had been under surveillance and was arrested on Nov. 2 at a hideout in Ikorodu, a district on the outskirts of Lagos state. He was found to have two AK-47 rifles.

He identified an accomplice who was followed by police on Dec. 26 but who abandoned his car in Ikorodu and fled. Explosives and detonation equipment were found in his car.

Awunah said the attack on the bridge would have caused major devastation. “Further investigation is being intensified to arrest all the other members of the militant gang still at large,” he said.

(Reporting by Alexis Akwagyiram; editing by Susan Thomas)