The Haftar-led Libyan National Army (LNA) are conducting airstrikes on targets in Tripoli, LNA operation headquarters' press service reported.
The LNA also said that it had destroyed the Government of National Accord's operational headquarters.
Earlier in the day, Reuters reported that according to a tape published by Haftar's spokesman on Sunday, the field marshal said that Ramadan, the holy month of fasting, which starts this Monday in Libya, was a month of holy war.
READ MORE: Over 340 Killed, 1,652 Injured Since Start of LNA Offensive on Tripoli — WHO
Since the overthrow and killing of Libya's long-time leader Muammar Gaddafi in 2011 Libya has been divided into two parts — the internationally recognised GNA headed by Fayez Sarraj in Tripoli and a parallel administration allied to Haftar in the east of the country.