Libya's internationally recognized government forces neutralized at least 10 members of putschist Gen. Khalifa Haftar's militia in shelling Sunday, while the capital was shaken with a withering bombardment by the warlord’s forces.

The army destroyed four observation posts on the Mashru front in southern Tripoli, killing or wounding a total of 18 militia and mercenaries, the media office of the government-led Burkan Al-Ghadab (Volcano of Rage) operation said in a statement.

Haftar’s forces bombarded the capital, threatening the main water supply in the capital, Reuters reported. The main water supplier to northwest Libya said armed men in the south had stormed one of its facilities, reducing supply.

"My father said we should be ready to leave at any moment ... the fighting last night was heavier than at any time before," said a resident of Abu Salim district, near a frontline.

"We would leave to survive, but where can we go? ... We will be on the street. It's hopeless," the resident added over the phone.

Haftar's forces have been trying to capture Tripoli for 13 months, but Turkish military aid this year for the internationally recognized Government of National Accord (GNA) has helped it regain some ground.

Haftar, backed by the United Arab Emirates, Egypt and Russia, last week announced a new air campaign but most bombardment since then has been through artillery.

Last month pro-GNA forces recaptured a string of towns in the northwest of Haftar's position, reestablishing their control between Tripoli and the Tunisian border.

Tripoli residents described the bombardment as the worst so far after weeks of fighting as the GNA attempts to end Haftar's campaign to seize the capital and push his forces out of artillery range.

Mitiga International Airport, the only functioning airport in the Libyan capital, was targeted by rockets for a second day after shelling on Saturday destroyed fuel tanks and sprayed shrapnel across a passenger jet being readied for takeoff.

The U.N. Libya mission condemned what it called "indiscriminate attacks," which it said were mostly attributable to pro-Haftar forces. It said last month that the Haftar militia was responsible for four-fifths of civilian deaths in the first quarter of 2020.

Water pressure in Tripoli was already starting to decline on Sunday afternoon after the Great Man-Made River project, the main water utility, said one of its power stations in the south had been stormed by armed men.

Ahmed al-Deeb, head of its western region committee, said the men had switched off the electricity because of a shortage of cooking gas and a lack of cash in local banks, and that tribal elders were negotiating with them to restore power.

The state-run National Oil Corporation said last week it was carrying out work to supply cooking gas from the country's main Sharara oil field.

On Saturday, at least six civilians were killed when Haftar's militia launched rocket attacks on Mitiga International Airport in the capital.

The attacks came hours after the U.N. Support Mission in Libya (UNSMIL) condemned indiscriminate attacks on civilians in Tripoli, saying they "may amount to war crimes."

The Turkish Foreign Ministry also condemned the Haftar attacks, saying that they amount to war crimes, adding that Haftar elements will be considered legitimate targets if they continue to threaten Turkey's interests in the country.

"On this occasion, we reiterate that if our interests are targeted with our representative offices in Libya, we will consider Haftar elements as a legitimate target," it said.

"It is unacceptable for the United Nations to remain immobile any longer in the face of this brutality," the statement added, stressing that the international community has the responsibility to stop Haftar from killing women, children and the elderly during the holy month of Ramadan and amid the coronavirus pandemic.

Haftar, the leader of illegal armed forces in eastern Libya, has intensified attacks on civilians since the beginning of May as the Libyan army recently gained an advantage and inflicted severe losses on his militants.

The government has been under attack by Haftar's forces since April 2019, with more than 1,000 killed in the violence. It launched Operation Peace Storm on March 26 to counter attacks on the capital.

Following the ouster of late ruler Moammar Gadhafi in 2011, Libya's government was founded in 2015 under a U.N.-led political deal.