The new Police Ombudsman for Northern Ireland has said she is "deeply concerned" by the number of investigations involving officers accused of abusing their position for sexual purposes.

Jacqui Durkin said these account for 36% of her office's most serious cases, and one of the investigations involves a former officer who was arrested last year on suspicion of rape and dozens of other alleged offences.

Durkin, who was appointed in June, told BBC News NI that the cases are among her top priorities.

Last year, a report by the ombudsman's office highlighted the issue of APSP, or abuse of position for sexual purposes.

"Thirty-six percent of our most serious investigations are those involving abuse of position for sexual purposes and that's deeply concerning," Durkin said.

"It's very difficult to comment on why it's increasing.

"The chief constable [Jon Boutcher] has said very publicly it is a serious form of corruption.

"I share those views."

Durkin has taken over from Marie Anderson, whose last two years in post were overshadowed by a police investigation into potential misconduct in office.

Anderson was not charged with any offence.

"The work of the office has gone on despite the challenges over the last couple of years," Durkin stated.

"But I am mindful that it is incumbent on me to build more public confidence and more police confidence in the office.

"That is what I am planning to do."

Her office has more than 100 staff and an annual budget of about £12m.

Durkin said she has made the Department of Justice (DoJ) aware of the "pressures" the office is under.

The police ombudsman added that Troubles legacy cases currently present "acute financial challenge".