Police in Northern Ireland are investigating 21 of their officers, staff and contractors who are suspected of "productivity spoofing," Deputy Chief Constable Bobby Singleton has said.

In a letter to Policing Board members, Singleton said Operation Akarpos has been launched to guard against abuse of remote working and to ensure the productivity of staff.

The Anti-Corruption Unit (ACU), which is carrying out the inquiry, has found "no systemic abuse of home working by Police Service of Northern Ireland (PSNI) officers and staff".

Singleton said the "activity/productivity spoofing" can include taking steps to make users appears active when they are away from their laptops.

Individuals' privileges have been amended where working from home is unavoidable or removed where it is not, Singleton explained.

"As an under-resourced and funded service we want the board to be assured that we will not tolerate inefficiency but dishonesty even more so," he said.

"Our communities need to see value for public money and resources, especially when we are asking the Northern Ireland Executive and British government for additional funding."

The investigation, which was first revealed in the Irish News and the Belfast Telegraph on Thursday, has been welcomed by politicians.

Social Democratic and Labour Party (SDLP) MLA Colin McGrath said remote working can be positive and "it would be unfair if the suspected actions of a very small number were allowed to undermine it".

"The public rightly expects officers and staff to be working when they are being paid to work, particularly when the PSNI is under significant financial and staffing pressure," he said.

During the Covid-19 pandemic, remote working was introduced for PSNI officers and staff, which Singleton said "kept the service working and our workforce and communities safe".

In a post-pandemic era, the PSNI is "keen to retain remote-working capability across the service," he added.

Ulster Unionist Party (UUP) leader Jon Burrows said it was "right that there are checks in place that people aren't spoofing".

"If the PSNI think people are sitting at home, pretending to work when they're not, I support them in taking action to identify that," he told BBC Radio Ulster's The Nolan Show.

Burrows added that he would support the supervision of other public service workers working from home and where productivity is not in line with where it should be.