Former security guards at a vast Del Monte pineapple farm in Kenya have for the first time described violent clashes between guards and thieves at the plantation, which is facing civil claims over allegations of killing, rape and beatings by its guards.

This month Del Monte announced it would outsource its security operations at the farm to G4S, sacking its 214 in-house guards.

The decision followed a series of investigations by the Guardian and the Bureau of Investigative Journalism since June last year that uncovered allegations of multiple deaths and violence linked to Del Monte’s guards.

Del Monte said G4S was given the contract in response to the recommendations of a recent Human Rights Impact Assessment, which was commissioned after the reporting. G4S will deploy 270 guards on the farm and it says they will be given extensive training, including on de-escalation techniques and the minimum use of force.

In interviews with the Guardian, five former guards at the farm alleged that a lack of training and Del Monte’s poor relationship with local people had fuelled violent clashes.

One former guard, who worked for Del Monte for 10 years until 2019, claimed he saw suspected trespassers mauled by Del Monte’s dogs, get injured from beatings by guards or being hit by Del Monte cars then dumped in the bushes near the main road. He said he knew some were found alive and rescued while in other cases, he did not know what happened to them.

“I started feeling that this was not the right job for me, just like my mother had kept telling me, because I come from the local area and I saw many people that I know suffer under the hands of the guards,” the former guard said.

He claimed stolen pineapples had been sold by the senior guards, which was “big business”, and that commanders had moved patrol teams away from where they intended to sell them.

Another former senior guard who worked at the farm for 13 years before losing his job in the G4S changeover, said when he started he was issued with a baton and given “basic training” on how to apprehend trespassers, “which was largely physical training”.

He said it was not until mid 2023 that they were told to “use minimum force”. The change of approach appears to coincide with the publication of the first Guardian and TBIJ articles alleging excessive violence by guards in June 2023.

The guard said “the surrounding community was quite violent and they kept attacking us”, adding: “I blame it on the company for failing to establish a good relationship with the community who felt that they had no benefit from Del Monte.”

He said thieves were “well informed about the farm and knew where pineapples were ripe” and that thieves had insiders at the farm who gave them so much information “that they stayed ahead of the game most of the time. Sometimes they had more information than we did.”

Guards described how a newly introduced security manager left last month and two zone managers were sacked after reports that four men died after going to steal pineapples in December. The Guardian reported last month that representatives of Del Monte Kenya were accused of offering bribes in an attempt to cover up the circumstances.

Many of the former guards have been protesting outside Del Monte, alleging that they were sacked without warning. A Del Monte spokesperson said the terminations “were conducted in accordance with Kenyan law and in consultation with the union”.

A high court hearing on Thursday granted permission to lawyers for families bringing a civil claim against Del Monte to amend their case. They are expected to add thousands of additional claimants.

Fresh Del Monte, the Florida-based headquarters of the tropical fruit empire, is arguing that it should not be liable for a case in Kenya because it is domiciled in the Cayman Islands. Its subsidiary, Del Monte Kenya, has not opposed being named and intends to respond to the allegations.

A spokesperson for Del Monte Kenya said: “Del Monte Kenya welcomes this opportunity to address the allegations that have been levelled against us and the Kenyan government in the appropriate venue, which is the Kenyan courts and not the media.”

Mwangi Macharia, chair of the African Centre for Corrective and Preventive Action, which is bringing a civil claim against Del Monte on behalf of families, said: “What we see in the change of guards at Del Monte is an admission that their guards were involved in the human rights violations and a major vindication to us who have been dismissed whenever we made these allegations.

“I think it is also irresponsible to just replace the guards with G4S security because that will not change much without proper community engagement. There is supposed to be stakeholders’ dialogue. Changing guards without addressing these issues will still bring us problems as human rights defenders.”

A Del Monte Kenya spokesperson said G4S was given the contract because of the Human Rights Impact Assessment’s recommendation and “not as part of any kind of admission of wrongdoing”.

They added: “We understand that the allegations that have been reported in the media, pointing blame on Del Monte Kenya, are part of a widespread disinformation campaign designed to pressure Del Monte Kenya to cede land that legally belongs to it. The constitutional action that has been filed against the attorney general of Kenya and the director of public prosecutions of Kenya as well as Del Monte Kenya and others is by the same self-interested organisations that have been calling for Del Monte Kenya to cede land that it legally owns.

“The court case is an opportunity for all parties to present evidence – rather than unsubstantiated allegations – in a public forum and we trust that those proceedings will reveal the truth and vindicate our good name.”

G4S declined to comment.