A murder suspect tried to hand himself in at a police station but had to phone officers instead because the front desk was closed.
The 51-year-old arrived at the building in John Street, Brighton, East Sussex, at 6am on Thursday, only to find the counter - where the public report crime - was not open until 8am.
He then proceeded to phone 999 while standing outside and officers later found the body of 46-year-old Samaritans volunteer Jillian Howell at a house in Sandgate Road.
She had been stabbed multiple times and was pronounced dead at the scene, police said.
Her family paid tribute to her in a statement which said: "Jill was a kind, gentle and loving sister, aunty and friend. We are shocked and heartbroken by her loss.
"She touched many lives in her volunteer work and was always helping others. She loved to travel, was a passionate Brighton and Hove Albion fan and season ticket holder.
"She lived life to the fullest and was dearly loved by her friends and family."
A Sussex Police spokesman said: "The man called 999 from outside the police station in John Street, Brighton, which is operational 24 hours a day.
"The time from when officers were deployed to when they were with the man was less than a minute.
"The front desk of the station was not open at the time that the man called, but this would not have made any difference to the response time."