Ottawa – A message of condolence from Queen Elizabeth II and musical tributes for the victims of the worst mass shooting in Canadian history poured in on Tuesday as the death toll rose to 23.The Royal Canadian Mounted Police (RCMP) said new human remains were discovered in homes and vehicles set ablaze by the suspect during the weekend killing spree in Nova Scotia."We believe there to be 23 victims, including a 17-year-old (girl). All other victims are adults, both men and women," the RCMP said in a statement. "We have recovered remains from some of the locations of the fires."The RCMP did not specify if the shooter was among those counted, and could not be immediately reached for clarification.The gunman, identified as 51-year-old Gabriel Wortman, launched his rampage late on Saturday in the seaside village of Portapique.He died roughly 14 hours later after being shot by police at a gas station outside Halifax, 100km away.Queen Elizabeth II said she and Prince Philip were "deeply saddened by the appalling events in Nova Scotia".Motive still a mysteryThe monarch, Canada's head of state, also paid tribute to the RCMP officers – one of whom died – and others who "selflessly responded to these devastating attacks".Across Canada, flags flew at half-mast, while Prime Minister Justin Trudeau proclaimed: "Today we are all Nova Scotians."He recounted how members of his RCMP security detail knew and remembered fondly Constable Heidi Stevenson, who was killed while responding to the shootings."It really goes to show just how tightly knit not just the RCMP is as a force, but how close we are as a country," Trudeau said.Other victims identified were a young father, a woman who twice previously beat cancer, a pregnant woman, a nurse, an elementary school teacher, prison guards and a retired firefighter.Among the dead were also two elderly couples who had recently retired and moved from Toronto – Canada's largest metropolis – into cottages in the quiet Nova Scotia towns.The assailant's motive was still a mystery. Media reports said Wortman was a denturist who owned clinics in Halifax and Dartmouth that were closed under the pandemic lockdown.The shooter was also reportedly obsessed with policing, having refurbished several old squad cars, and struggled with alcoholism.Searching 16 crime scenesIn an update on their investigation, police said Wortman wore an "authentic police uniform" during the shootings but that the vehicle he drove from town to town was a "replica" police car.A search for evidence, they added, was ongoing at 16 locations in the towns of Portapique, Wentworth, Debert, Shubenacadie, Milford and Enfield.A "virtual vigil" was planned for Friday evening, but several have already popped up on social media.Residents are unable to gather for in-person services due to coronavirus restrictions on large gatherings.A plane's flight path – shown on tracker website FlightAware – marked a heart shape over the Atlantic coast towns in a sign of mourning."I wanted to reach out to the community. I wanted to be there with them. I wanted to tell them that I love them," pilot Dimitri Neonakis told public broadcaster CBC, adding that because of social distancing, "my only avenue was through the air".'Gentle tune' for Nova ScotiansA church in Banff rang its bells to the tune of "Farewell to Nova Scotia".The Canadian rock band Northern Pikes and others also posted online bagpipes and acoustic guitar versions of "Amazing Grace", while Toronto-based Choir! Choir! Choir! planned to lead an online rendition of Leonard Cohen's "Hallelujah" on Tuesday.And Winnipeg musician Scott Nolan wrote a new "gentle tune" for Nova Scotians."Tonight I grieve for sons and daughters who never got to say goodbye... from Portapique to Shubenacadie, no one here will forget today," he sang."The neighbour said he couldn't believe it... I thought I heard distant sirens, I see fire down the road, we can still hear the gunshots, at night it's hard to be alone."