Candles were lit at a Fredericton vigil Friday as as a sign of solidarity as the city mourns the deaths of two police officers and a man and woman who were killed earlier in the day.

"We stand together and we stood together today," Bishop David Edwards said to those gathered.

The vigil was held at St. John the Evangelist Anglican Church on the city's north side, not far from the scene of the shootings.

"Sometimes all we can do is stand together in the darkness," Edwards said.

He asked people to quietly reflect as they remembered those who were killed. Many could be seen wiping away tears during the service.

In addition to readings and hymns, Edwards and other clergy prayed for all those involved.

And even after the vigil ended, people were welcomed to stay and told the church would be open as long as they wanted to stay.

Earlier in the day Edwards said it was hard to believe this is happening in New Brunswick at all.

"My hope is that we'll come together in support of each other."

At the vigil, Edwards expressed surprise at the number who attended the service.

It's part of an outpouring of support for those affected by the shooting.

Cards, flowers and a teddy bear have been left around a sign outside the Fredericton Police Force's downtown headquarters. Many people, including police, also gathered outside the hospital in Fredericton.

A card left with flowers outside the Fredericton Police Force headquarters on Friday. (Julia Wright/CBC)

'Sad day in Canadian policing'

The shooting has prompted an outpouring of support and grief from police forces across the country.

Chief Jean-Michel Blais of Halifax regional police said in a post on Twitter that the force will fly the New Brunswick flag outside its headquarters.

Our thoughts are with everyone in Fredericton. We mourn for those lives lost and the devastation to the community. Thank you to our brothers and sisters in blue with <a href="https://twitter.com/CityFredPolice?ref_src=twsrc%5Etfw">@cityfredpolice</a> who are protecting their city. We are so sorry for the loss of two of your own. We stand with you. —@edmontonpolice

Blais said he spoke to Fredericton Chief Leanne Fitch earlier on Friday "to offer her any support we can give."

In a post on Twitter, Adam Palmer, chief of the Vancouver police, called it a "very sad day in Canadian policing."

RCMP in New Brunswick also offered condolences. Three RCMP members were killed and two injured in Moncton on June 4, 2014.

The RCMP in New Brunswick offers its condolences to the families and friends of the four people killed in Fredericton this morning and to our police colleagues with the <a href="https://twitter.com/CityFredPolice?ref_src=twsrc%5Etfw">@CityFredPolice</a>. —@RCMPNB The <a href="https://twitter.com/hashtag/RCMP?src=hash&ref_src=twsrc%5Etfw">#RCMP</a> offers heartfelt condolences to the families, friends and colleagues of the victims and fallen officers involved in this morning's tragic shooting in Fredericton. Thanks to <a href="https://twitter.com/CityFredPolice?ref_src=twsrc%5Etfw">@CityFredPolice</a> and the first responders who continue their work in the wake of this tragedy. —@CommrRCMPGRC

The bishop said the shooting was the first event of this nature that has occurred since he assumed his post more than three years ago.

Within about half an hour of hearing the news, Edwards said, he knew some kind of event to bring people together would be needed.

He offered condolences to the families of those affected by the shooting.