A plane of Wings Air on the Kupang-Wunopito Lembata route with 40 passengers was supposed to land at Wunopito Airport at 11 a.m. local time, but the pilot decided to return to the departure airport, Xinhua news agency reported.

"The pilot saw indications of volcanic ash near the landing strip, so he took the plane back to Kupang, for security reasons," said head of Wunopito Airport Muhammad Syaiful Zuhri.

This is the third time that planes have failed to land at Wunopito Airport due to volcanic ash, added Zuhri. Previously, the same incidents occurred on May 7 and May 14.

The mountain released one earthquake eruption and 102 earthquake gusts since 06.00 a.m. to 12.00 p.m. local time, according to the Ile Lewotolok Volcano Monitoring Post.