A heartbroken husband has paid tribute to his wife after seeing her killed by a pickup truck while cycling in Thailand.

Christian missionary Marine Scott, 49, was riding with her husband Joe, 50, on a wedding anniversary trip with their two daughters when the vehicle smashed into her in Kanchanaburi, western Thailand.

The experienced cyclist - who had competed in events and was wearing a helmet - was killed instantly on Saturday morning shortly before 7.30 am. The force of the impact ripped her leg and arm from her torso.

Devastated husband Joe collapsed in tears on the roadside as police and paramedics comforted him.

Grief-stricken Joe said his wife, from Sault in Ontario, Canada, was ‘hit by a car while crossing the road on her bicycle'.

The father-of-two said: 'I'll never unsee this. I saw her heart, and I saw its last beats. I'm so confused and hurt and I can't stop sobbing.

'We were out for a bike ride. She really wanted to go today. I was hesitant, but I agreed.

‘This woman was my everything. I'm so broken. Marine was my world. My best friend since 13.'

Joe and Marine had been working for more than a decade in northern Thailand close to Myanmar, where they carried out missionary work for the Christian Freedom International in Front Royal, Vancouver. Their work focused on helping Christians persecuted and they had built a number of schools.

The married couple left their home in Mae Sot, Tak province, for a trip to Kanchanaburi with their two daughters, Maija and Kiera. They celebrated their wedding anniversary on June 15 just three days before the crash. The night before the accident, Marine had posted pictures from their river raft.

Marine was an experienced cyclist having competed in a number of events around Thailand and was familiar with the country's roads. She regularly cycled around the country.

However, police said they received an emergency call at around 7:30 am local time informing them that a tourist had been ‘killed by car'.

Police Captain Chairat Jananan, Deputy Inspector of Investigation at the Muang Kanchanaburi Police Station, travelled to the scene.

The policeman said Joe was crying on the roadside.

Police Captain Chairat added: ‘On the left side of the road, the body of the deceased was found, a foreign woman lying on her back.

‘Nearby, the bike of the deceased was also found, which had been smashed up and overturned.

‘Joseph Micheal Scott, 50, a Canadian, was sat crying next to the dead body. The deceased was his wife.'

Police said that Joe and Marine had cycled out onto the road from the driveway at the resort where they were staying. Joe was in front of Marine and crossed the road first.

Marine pushed off from the junction and was cycling over to the middle u-turn point to reach the other side when a grey Isuzu pick-up truck crashed into her.

The driver Chaiyawat Choto, 23, told police at the roadside that he was retiring from running errands when he saw Marine move out into the road in front of him.

He said: ‘I saw the foreign man first reach the other side of then road then I saw a foreign woman on a bicycle. I was driving at high speed and honked the horn to warn her but she still moved off the roadside.'

Officers held Chaiwat in custody at the Muang Kanchanaburi Provincial Police Station to be interviewed.

Police Captain Chairat added: ‘We have further questions to ask the suspect before any allegations are filed against him. We have to also check cameras and evidence from the scene.'

Police said that the Canadian Embassy had been informed of the death and would be assisting Joe.