Searches have been carried out at several premises in Waterford after four members of the same family were killed in an arson attack in the city.

Kim English, Philip English and two of their children - nine-year-old Jayden and 12-year-old Callum - died after their home in Birch Avenue was set on fire on Tuesday.

Gardaí (Irish police) described the investigation into their murders as "intense in nature and very active".

They said "multiple searches" were conducted on Tuesday evening and vehicles and electronic devices have been seized for technical examination.

Six members of the English family were sleeping when their home was attacked in the early hours of Tuesday.

It is believed that an incendiary device, likely a petrol bomb, set the house on fire.

Two children were severely injured in the blaze and were taken to a Dublin hospital where they both remain in a critical condition.

Members of the community have been supporting their relatives and some have been sharing poignant memories of those who did not survive.

For the past five years, Callum played for Johnville FC, a schoolboy and junior football club in Waterford.

His coach Alex O'Sullivan told BBC News NI that he was a "fantastic player" and a "lovely kid" both on and off the pitch.

"Great sense of humour... always happy. Helpful to his teammates and coaches. There was never any cheek coming from Callum.

"You'd often see him on the street and he'd be waving, 'Hello coach', and you'd get a little chat out of him, and he always had a great smile on his face."

O'Sullivan said he first met Callum when he was playing under-11s football.

"Callum was always there. Same with matches, he loved coming to the matches."

O'Sullivan said he also got to know the boy's parents Phillip and Kim, from dropping Callum off to training and supporting him when he was playing.

"They were always there to show up."

Jayden was born with a heart condition and travelled to appointments in Dublin by BUMBLEance, a children's ambulance service.

Waterford based paramedic Áine Phelan worked with the service and had travelled with Jayden to his appointments, Irish broadcaster RTÉ has reported.

She told the broadcaster it was an "absolute privilege" to accompany Jayden and she was trying to comprehend what has happened.

Phelan added that her thoughts are with the family in the "sad, sad days ahead".

Amanda Powney was friends with Kim and Phillip, and her son got the school bus with Jayden.

Powney said she looked after the children so she has "known them since they were tiny tots".

She described Jayden as a happy boy adding that he was "full of his fun", adding that it the situation is "very sad".

The community in Waterford city is in shock following the fatal fire which claimed four lives.

Butler's Community Centre is operating a drop-in service for any members of the community who may need support or help to process the grief.

Normally, the community centre is a location for sporting, cultural and family events. But on Tuesday it has been turned into a service to support the grieving community.

Supports on offer include the Health Service Executive (HSE) and charities Bernardos and Jigsaw as well as the local council.

The centre is just a stone's throw from Birchwood, the estate where the family lived.

Neighbours brought flowers to the house and passed them onto gardaí who are still preserving the scene. They were visibly emotional and shaken as they gathered in small groups around the estate.

James English, who was 12-year-old Callum's godfather said the family is "not too good".

"We have a loss of a family now, wiped out. Please whoever done it, own up," he told reporters.

There are many gardai and investigating officers at the estate as the murder investigation continues.

The Catholic Diocese of Waterford and Lismore has confirmed that a vigil will be held at Sacred Heart Church on Wednesday.

It said the vigil will provide an opportunity for people to "come together in prayer for those who have lost their lives, their grieving families and loved ones, and all those affected by this terrible tragedy".

Gardaí launched an investigation on Tuesday, describing it as a "multiple murder and arson attack".

RTÉ is reporting that detectives believe the attack is linked to organised crime and drugs-related intimidation.

No arrests have been made.

On Wednesday, Ch Supt Anthony Pettit said: "There are people in the community who know the person or persons who carried out this arson attack in which four people have been murdered."

He appealed for them to contact the investigation team, which is based at Waterford Garda Station.

On Tuesday morning, firefighters, ambulance staff and gardaí all responded to the emergency at the family home in the Birchwood housing estate, about 3km (1.8 miles) outside Waterford city centre.

Waterford Fire Service said it was alerted to the fire at 05:13 local time and its crews arrived to a well-developed fire at a two-storey house.

It said a number of casualties were removed from the house before the blaze was extinguished and the scene was handed over to gardaí.

On Tuesday afternoon, Ch Supt Pettit said officers believe the house "was attacked by a person or persons unknown and that the fire was started deliberately".

He appealed to anyone who was in the vicinity of the Birchwood housing estate between 04.30 and 05.30 local time on Tuesday morning to contact gardaí.