A senior CPS prosecutor has said there is no evidence that an attempt was made to hijack or endanger an oil tanker during an incident off the Isle of Wight.

The statement by Joanne Jakymec, chief prosecutor for the Crown Prosecution Service (CPS) Wessex, comes after the Home Office criticised a decision to drop the prosecution against seven Nigerian men detained aboard the Nave Andromeda by British special forces.

Two men, Matthew John Okorie, 25, and Sunday Sylvester, 22, had been charged with an offence relating to conduct endangering ships under Section 58 of the Merchant Shipping Act 1995, but their charges have now been dropped.

Five others were awaiting a decision by the CPS when the prosecutors advised Hampshire police not to charge.

The Home Office criticised the move in a statement saying: “We are disappointed by this decision. It is frustrating that there will be no prosecution in relation to this very serious incident and the British people will struggle to understand how this can be the case.

“The Home Office is working with the CPS urgently to resolve the issues raised by this case.

“The immigration cases will be dealt with as quickly as possible and removal action will be pursued against anyone who has no right to remain in the UK.”

Ms Jakymec said the decision was made following new evidence on the incident leading to the detention of the seven Nigerian men on October 25, including from mobile phone footage, witness statements and maritime expert evidence.

She said: “While initial reports had indicated there was a risk of destruction or serious damage to the ship and risk of harm to the crew, additional mobile phone footage made available to us by the police subsequently, together with further expert analysis of the evidence, cast doubt on whether the ship or the crew were in fact put in danger.

“As the evidence, when made available and fully considered, could not show that the ship or crew were threatened while in UK waters, the legal test for the offence of conduct endangering ships under s.58 Merchant Shipping Act 1995 was no longer met and we discontinued the case.”

She added that the charges against Mr Okorie and Mr Sylvester had been made on initial evidence which could no longer be relied upon.

Bella Sankey, director of Detention Action, said: “It is concerning that the Home Office is publicly criticising a decision by our independent crown prosecution service.

“In this case, on the evidence that has been provided the CPS have concluded that there is insufficient evidence to show the crew and ship were put in danger and there is no realistic prospect of conviction.

“Political interference with the administration of justice undermines the Rule of Law and any attempt to discredit a decision reached by the CPS, or to apply pressure to them, is abusive and unwelcome.”

The SBS raid was authorised by Defence Secretary Ben Wallace and Home Secretary Priti Patel following a 10-hour stand-off while the tanker remained off the Isle of Wight.

The 748ft (228m) Nave Andromeda had been heading towards Southampton, having set sail from Lagos in Nigeria.

The ship’s operator, Navios Tanker Management, said the stowaways “illegally boarded” the Liberian-flagged tanker in Lagos.

A Hampshire police spokesman said the seven men would remain detained subject to immigration procedures.