Aljazeera's correspondent in Beirut, Abbas Nasir, said a large explosion shook Jounieh, 15km north of Beirut, near the main square of the picturesque town late on Friday.
The 25kg bomb destroyed the headquarters of religious radio station Sawt al-Mahaba, which belongs to the Maronite Church, and severely damaged the adjacent Mar Yuhanna Church in the town's souk.
Three hours after the explosion, rescuers pulled a wounded man from the rubble.
Police officials could not immediately tell whether the bomb was placed in, under, or next to a car on the street.
Christian leader's return
The bombing came hours before the outspoken anti-Syrian Christian leader General Michel Aoun was to return to Lebanon from a 14-year exile in France.
Aoun said the bombing was
not related to his return
Aoun, speaking to Aljazeera before he left from Paris, said he did not think the bombing was related to his return.
"The explosion is not a message to me, but an attack against Lebanese people who want to practise their lives naturally," Aoun said.
"Unfortunately, some people feel harmed by the return of stability and normal life to Lebanon, as they have stolen its properties for 30 years," he said.
"Let Lebanon live and build itself. Thirty years of terrorism, destruction and killings are enough," he said.
The explosion broke a lull of several weeks after a spate of bombings of commercial structures in Christian areas and opposition strongholds.
Bombings in March and early April killed three people and injured 24.
Speaking to Aljazeera from Beirut, Lebanese Druze leader Walid Jumblatt accused the Lebanese government and Lebanon's President Emile Lahoud of being responsible for the series of explosions that have taken place recently.
Supporters of Michel Aoun are
awaiting his return on Saturday
Lebanon has been in political turmoil since a massive bombing in the capital on 14 February killed former prime minister Rafiq al-Hariri, the country's most famous politician, and 20 others.
Subsequently, mass anti-Syrian protests and intense international pressure forced Syria to withdraw its troops.
Syrian forces completed their withdrawal on 26 April and a new government was installed in Beirut last month.
The country is to hold crucial parliamentary elections beginning on 29 May.