A magnitude 6.1 earthquake struck off the shore of Indonesia's Java island on Friday, at a depth of 10km, Indonesia's geophysics agency (BKMG) said.
The epicentre was located 132 km north of Tuban in East Java province, BMKG said.
The tremors were felt strongly in East Java, its capital Surabaya, as well as cities in neighboring provinces, according to multiple postings by social media users in those areas.
The quake has no potential to trigger a tsunami, BMKG said.
There were no immediate reports of damage.

Trump gets royal welcome in Japan, China trade truce hopes rise
Rubio says Israeli strike on Gaza didn't violate ceasefire
Trump says he would not run for vice president in 2028
Two climbers die in Nepal after expeditions to Ama Dablam mountain
