GENEVA, Jan. 29 (Xinhua) -- The United Nations human rights office expressed deep concern on Tuesday about an "extremely violent" attack on Palestinians in the West Bank village of Al-Mughayyir, in which a 38-year-old Palestinian father of four was shot in the back and died.

The father, Hamdi Taleb Na'asan, was shot on Jan. 26, said Rupert Colville, spokesperson for the UN High Commissioner for Human Rights (UNHCR), at a media briefing here.

"The monitoring by our staff in the West Bank suggests that the killing took place after a group of up to 30 Israelis -- some of them armed -- from the nearby Israeli outpost of Adei Ad first of all attacked Palestinian farmers in their fields," said Colville.

The attackers then descended on the village itself, where they used live ammunition to shoot at the villagers and their houses, said the spokesperson.

He said the confrontation led to six villagers being shot with live ammunition, leaving three of them in a serious condition.

It is unclear whether any settlers were also injured.

"Although Israeli security forces were stationed near the village and were immediately alerted to the attack, witnesses informed our staff -- who visited the village yesterday -- that it took some two hours before they intervened," said Colville.

When Israeli security forces did finally intervene, the UN human rights office said it appears they focused mainly on dispersing the Palestinian villagers using tear gas.

Three more Palestinians were injured by live ammunition after the intervention by the security forces.

"However, it is not clear at this point whether they were shot by settlers or by soldiers," said Colville, noting that a total of 20 villagers were injured on Jan. 26.

Villagers in Al-Mughayyir have faced attacks and harassment in the past, he said.

According to the United Nations Office for the Coordination of Humanitarian Affairs (OCHA), the average number of violent incidents instigated by settlers each month increased 57 percent in 2018 compared to 2017, and by 175 percent in comparison with 2016.

The UN human rights office said that Israel is the "occupying power" and is obliged under international humanitarian law to protect the Palestinian population from such attacks.