Jakarta – Police in Central Java are investigating two attacks on churches in the lead-up to Christmas.

Central Java Deputy Police Chief Brig. Gen. Sabar Raharjo told Metro TV that unknown assailants threw Molotov cocktails at the Jesus The King Catholic Church in Sukoharjo, Solo, on Tuesday. No injuries were reported but the church's wall was damaged.

In a second attack on Sunday, though only reported on Wednesday, shots were fired through the windows of the Indonesia Muria Christian Church (GKMI) in the city of Solo.

Church official Sri Sarsiyah told Detik.com that they had filed a police report, complete with bullet fragments as evidence, and had sought police protection.

The church, on Jalan Kedempel 14, has a congregation of between 110 and 130 people. "We are still checking so we don't know anything yet," Central Java Police Insp. Gen. Edward Aritonang told Detik.com.

Sabar said two crude homemade bombs were also discovered outside the Pasar Kliwon Police Precinct in Solo on Tuesday.

Extremists in Indonesia have in the past used terrorist attacks over the Christmas period to foment anger between Muslims and Christians.