A 26-year-old man has been arrested in Dublin on suspicion of the murder of Mary Ward in Belfast.

The body of Ms Ward, 22, was found by police in Northern Ireland at her home in Melrose Street in Belfast on October 1. Three days later police formally determined that she had been murdered.

She was last seen alive on Wednesday 25 September, a day when she spent time in Dungannon, Co Tyrone, Grand Central Bus Station in Belfast and on Melrose Street.

Ms Ward had previously reported being the victim of an assault on September 4 and a suspect was arrested and questioned in relation to that incident.

The Police Service of Northern Ireland (PSNI) has referred its safeguarding response to that reported assault to the region’s independent police watchdog, the Police Ombudsman for Northern Ireland.

PSNI Assistant Chief Constable Davy Beck at PSNI HQ in Belfast (David Young/PA)

Confirming the arrest in Dublin on Wednesday, gardai said they had launched their own murder investigation.

“An Garda Siochana continues to work closely with the Police Service of Northern Ireland on this investigation,” the Garda statement added.

PSNI Assistant Chief Constable Davy Beck said officers were still working to establish the exact circumstances of Mary Ward’s death.

He said: “First of all, I’d like to express my deepest sympathies to Mary Ward’s family and friends who are experiencing unbearable suffering knowing that their loved one was taken from them in such a cruel way.”

He added: “I am appalled that there has been another murder of a woman in Northern Ireland.

“Mary is the fourth woman to be murdered in Northern Ireland in just six weeks.

“This is simply unacceptable and too many women are losing their lives at the hands of men.”

Mr Beck outlined the chronology of the PSNI’s interactions with Ms Ward. He said police believe she was killed around September 25.

“We received a call from the victim on September 4, we responded to that call within minutes, we spoke to the victim, and we recorded an interaction with the victim,” he said.

“On the basis of that interaction, we followed that up with an arrest of a suspect. That suspect was taken to custody and was interviewed in respect of those issues.

“What followed is the issue that concerns us in terms of the organisational response and, in essence, that risk assessment and decisions that were made thereafter in respect of how we dealt with that person.

“So that’s why we have made that open and transparent referral to the ombudsman (NI Police Ombudsman), and we will await their review of that situation and their considerations in respect of that.”

He added: “We had a victim who reported an issue to us. We engaged with that victim on that date and on a number of occasions following that, so we want to ensure we learn from those engagements and our considerations around how we protected that victim.”

Mr Beck said that when officers found Mary Ward’s body at her Melrose Street home in Belfast they had been calling there about a matter unrelated to her reported assault at the start of September.

He declined to confirm whether police initially believed her death may have been suicide.

“We dealt with Mary on September 4,” he said.

“We had a phone call from Mary on September 10. Officers called in an attempt to speak with Mary on September 24 and we spoke to her again on the phone on September 25.

“Officers attended totally unconnected to that incident, but following up on another unrelated matter, on October 1, and that’s when we observed a female crouched over against the upstairs front window of that house and located Mary deceased, unfortunately, within the property.

“We initiated an investigation into the unexplained and suspicious death. That investigation was led by detectives.

“That was a complex investigation, that involved scene examination, detailed forensics, post-mortem, which got us to the point where we were in a position to confirm that this was a murder on October 4.”

Mr Beck rejected the suggestion that police are not taking the issue of violence against women and girls seriously enough.

“I don’t accept that,” he told reporters at a press conference at PSNI headquarters in Belfast.

“I see evidence every day of my officers and staff taking these issues very, very seriously.

“I see evidence every day of us responding to the needs of victims right across Northern Ireland, and that will continue, but clearly where there are issues that may have been a concern to us, and indeed the community and the public, it’s right and proper that we make that referral (to the ombudsman) and have those examined independently of us to make that assessment.”

He added: “I’m appalled that, again, violence against women and girls continues.

“Clearly, we want to protect people. We’re here to protect people and we’re committed to doing everything we can to protect people that face these types of challenges and issues.”