The names of the 49 people killed in the worst mass shooting in modern US history have been read out outside the Pulse nightclub in Orlando, exactly one year after a gunman started firing during "Latin Night" at the gay club.

"I realise that gathering here in this place, at this hour, is beyond difficult," Orlando Mayor Buddy Dyer told survivors, victims' families, club employees and local officials during the private service.

"But I also know that the strength you've shown over the past year will carry you through today and in the future."

Glasgow Times:

Photo credit: Joe Burbank /Orlando Sentinel via AP. (PA)

The service began what would be almost 24 hours of observations to remember the victims and the dozens of Pulse patrons who were wounded when Omar Mateen opened fire and pledged allegiance to the Islamic State group.

He was eventually killed by police after a three-hour standoff on June 12 2016.

Later on Monday morning, hundreds of people dropped off flowers, drawings and cards at a memorial near Pulse.

Another midday service was held, followed by an evening gathering in the heart of Orlando and a final, music-filled late-night service at the nightclub.

"It still hurts, it's still very raw," said Erin Anderson, a friend and former co-worker of Pulse victim Xavier Serrano Rosado.

Jeannine Williams used to live within walking distance of Pulse and was a frequent visitor.

She had made plans to be there the night of the shooting but decided to go to another night club.

Glasgow Times:

Photo credit: Joe Burbank /Orlando Sentinel via AP. (PA)

"A year later I think the thing that is most important is this community and why I live here and why I'm so happy to live here," Ms Williams said through tears.

"The support we not only have from our city government, it's not fleeting support, it's not support on certain days. It's the way the community is.

"This is Orlando. This is why I just love living here."

At noon, church bells throughout the Orlando area rang 49 times.

Governor Rick Scott ordered US flags around Florida to be flown at half-staff and a giant rainbow flag would be unveiled at the Orange County government building.

At a midday service at the nightclub, Pulse owner Barbara Poma said when people ask her what has changed in her life since the tragedy, she tells them "everything".

But she said she is grateful for the outpouring of support.

She plans to build a memorial at the site of the nightclub, which has been closed since the tragedy.

"I miss Pulse," she said. "We are one Pulse. We are one love."

Local leaders said Mateen's act of hate caused an outpouring of love from Orlando and the wider world.

"What a terrorist tries to do is divide us," said US Senator Bill Nelson.

"Isn't it interesting it had the opposite effect? It brought us together in unity and love."

Monday's services culminated several days of events aimed at turning the grim anniversary into something positive.

A foot race was held over the weekend, and eight gay and lesbian students were awarded 4,900 US dollars (£3,900) towards their college studies by a local businessman.

Local officials have declared the one-year mark as a day of "love and kindness", and they are encouraging residents to volunteer or perform acts of compassion.

An exhibit of artwork collected from memorial sites set up around Orlando after the massacre will be shown at the Orange County History Centre.

Ms Poma is developing plans to build a memorial at the Pulse site.

Mateen's wife, Noor Salman, is facing charges of aiding and abetting and obstruction in federal court.

She has pleaded not guilty to helping her husband.