Halton’s police chief is speaking out after two off-duty officers were assaulted in Ottawa over the weekend in what he is describing as an “unprovoked” and “cowardly” attack.

The incident happened early Sunday morning in Ottawa’s ByWard Market neighbourhood, near York and William streets.

The unidentified victims were in the city to attend an annual national memorial for fallen police officers. They ended up being taken to a local hospital with serious injuries following the assault.

A 25-year-old man from Ottawa has since been arrested and charged with aggravated assault in connection with the incident.

Police, however, have said that they are still looking for “four or five” other people who may have been involved in the assault.

In a statement issued on Tuesday, Halton Regional Police Service (HRPS) Chief Stephen Tanner called what happened a “heinous act.”

“I am both shocked and appalled that, during our time there, a number of individuals in the ByWard Market area assaulted a group of or off-duty officers in what was, by all indications, a violent, unprovoked, and cowardly act,” he wrote.

In his statement, Tanner thanked the Ottawa Police Service for its “support and investigative work” and Ottawa Paramedic Service and hospital staff for the “exemplary care” they provided to the injured officers.

The police chief said that he is hopeful that the injured officers will make “swift and full recoveries” and that those responsible “will be identified and brought before the criminal justice system in due course.”

Ottawa police chief Eric Stubbs has previously said that there is no evidence to indicate that the suspects knew the two victims were police officers when they attacked them.

With files from CTV News Ottawa.