The Meteorology, Climatology and Geophysics office said the quake hit at 03.22 a.m. local time with epicenter 8.41 degrees on south latitude and 116.52 eastern longitude at a depth of 12 kilometers, northwest of the Lombok Timur District.
"The epicenter of the quake was at northwest of the district of Lombok Timur at a depth of 12 kilometers," head of the geophysics office in Mataram Agus Riyanto said.
Agus said according to the Shake Map and information from the people, the strongest jolt was felt in the districts of Lombok Timur, and Lombok Utara, West Nusa Tenggara Province.
"The people were asked to remain calm and would not be worried by rumors aired by irresponsible people," he said.
However, gripped by panic, the people rushed out of houses and other buildings. The people of Lombok have been hit by trauma after a series of major quakes which have devastated the island leaving more than 560 people killed.
Zuhriatul of Kelurahan Kebon Sari, in Mataram, said he was shocked by the strong tremor awakening him from sleep with his wife and children.
"I was awakened by strong jolt. I grabbed my children to rush out of my houses with my wife. Neighbors also did the same," he said.
The family chose to sleep in the guest room of their house with door remaining unlocked after earlier joining other people to sleep under a tent in open place.
Lombok has been hit by a series of major quake over the past six weeks. The first and more devastating quake with a magnitude of 6.3 on the Richter Scale hit on July 29, followed by one 7 on the Richter Scale a week later and another big quake 6.9 on the Richter Scale hit on August 20.
The island is still busy with reconstruction of houses, public buildings including hospitals, government office buildings and schools as well as tourist resorts.
Lombok, just across a narrow strait of the tourist island of Bali, begins to rely much on its fast growing tourism industry for income.
Reporting by Awaludin
Editing by Albert Saragih, Bustanudin