Kenya's national human rights agency has opened an inquiry into claims that security guards at a Del Monte pineapple plantation in Thika, which supplies a majority of British stores, had killed people and assaulted others.

Villager complaints of guard brutality at the plantation, including three suspected deaths in the previous four years, were revealed by a joint investigation by the Guardian and the Bureau of Investigative Journalism (TBIJ) earlier this week.

The Kenya National Commission on Human Rights (KNCHR) expressed that it was "greatly concerned and disturbed" by the reported instances of human rights breaches, The Guardian reported.

Del Monte was urged by the commission, created by a law passed by Kenyan lawmakers, to "take immediate actions to ensure effective remedy" for people who have reported acts of violence.

Earlier, Del Monte said stated that it took the accusations “extremely seriously” and initiated a “full and urgent” investigation into the allegations. It said it was committed to international standards of human rights.

The sizable plantation, which spans at least 40 sq km (15 sq miles), is directly responsible for 237 security guard jobs and is Kenya's top supplier of agricultural products to the rest of the globe. These supermarkets include Tesco, Sainsbury's, Asda, Waitrose, Ocado, and Morrisons. Tesco claimed to have halted all orders for goods derived from the farm while an inquiry is ongoing.

Among the reported deaths is the accusation that a 52-year-old man suffered injuries in December and passed away a week after four witnesse

Read more: Kenya's biggest school meals program to be launched in Africa