PHNOM PENH/BANGKOK/UNITED NATIONS - Thailand's military-run Channel 5 reported on Friday that clashes broke out at several areas along the Thailand-Cambodia border in the early hours of the day, saying Cambodian forces have conducted sustained bombardment utilizing heavy weapons, field artillery, and BM-21 rocket systems.

Thai forces responded with appropriate supporting fire in accordance with the tactical situation and issued advisories to local civilians to avoid entering areas of clashes.

Early Friday, the sound of artillery fire was heard again near the border area, the National Broadcasting Services of Thailand reported, citing a local official in Surin province.

According to the deputy spokesperson of the Thai Ministry of Public Health, 14 Thai people were killed and 46 others injured in military clashes near the Thailand-Cambodia border as of 9:00 pm local time on Thursday.

Cambodia's Oddar Meanchey deputy governor, Met Meas Pheakdey, told Xinhua over the telephone that one villager was killed and five others were wounded on Thursday when the Thai side fired artillery shells into Cambodian territory.

"More than 2,900 families living near the border have been evacuated to a safe refuge," he added.

"Fighting is still going on as of Friday morning," he said.

Cambodian Defense Ministry's Undersecretary of State and spokesperson, Lieutenant General Maly Socheata, said in a press briefing on Friday morning that the Thai troops had used heavy weapons and F-16 fighter jets as well as cluster bombs to attack several locations in the Cambodian provinces of Oddar Meanchey and Preah Vihear. 

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Also on Friday, the UN Security Council will hold a closed-door meeting on Thailand-Cambodia border clashes.

According to the Security Council program, the meeting, scheduled for 3 pm EDT Friday, was reportedly requested by Cambodian Prime Minister Hun Manet.

On Thursday, Cambodian Prime Minister Hun Manet urged the United Nations Security Council to convene an urgent meeting to discuss the matter.

In a letter to Pakistan's permanent representative to the UN Asim Iftikhar Ahmad, whose country assumed the rotating presidency of the Security Council for July, Hun Manet said that since early Thursday, Thai armed forces have launched attacks on Cambodian positions.

The attacks violated fundamental principles of international law, he said.

Hun Manet said Cambodia calls on Thailand to immediately cease all hostilities, withdraw its forces to its side of the border, and refrain from any further provocative actions which could escalate the situation.

Also on Thursday, Thailand's foreign ministry said the Thai government called on Cambodia to take responsibility for the incidents, cease attacks against civilian and military targets, and stop all actions that violate Thailand's sovereignty.

Otherwise, said the Thai foreign ministry in a statement, the Thai side is prepared to intensify self-defense measures in accordance with international law and relevant principles.

The Thai embassy in Cambodia has urged Thai nationals to leave Cambodia.

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Meanwhile, UN Secretary-General Antonio Guterres urged Thailand and Cambodia to exercise maximum restraint, a UN spokesman said Thursday.

"The Secretary-General is following with concern reports of armed clashes at the border between Cambodia and Thailand. The Secretary-General urges both sides to exercise maximum restraint and address any issues through dialogue and in a spirit of good neighbourliness, with a view to finding a lasting solution to the dispute," said Farhan Haq, deputy spokesperson for the UN chief, at a daily briefing.

14 Thai people killed 

Fourteen Thai people were killed and 46 others injured in military clashes near the Thailand-Cambodia border as of 9:00 p.m. local time on Thursday, the deputy spokesperson of the Ministry of Public Health said.

Cambodia had not released any information on its casualties as of Thursday evening.

The situation escalated following skirmishes that began Thursday morning. Each of the two sides blamed the other side for violating international law.

Hun Manet urged the UN Security Council to convene an urgent meeting to discuss the matter.