The husband of missing Hilary Ball was released by police today after questioning.

Geoff Ball, a 46-year-old unemployed IT worker, was arrested on Tuesday night on suspicion of murdering his 53-year-old wife.

After being held for more than 30 hours, Mr Ball was not charged and he was released with no bail terms attached.

Back at his home in Horsted Keynes, near Haywards Heath, he would not talk about his ordeal. Asked how he felt about being arrested, he said: "No comment.

"I have more important things to think about."

Meanwhile, specialist teams from around the country continued the search for Mrs Ball.

Specially-trained police from Wales and South Yorkshire are helping comb woods and fields near the couple's secluded home in Birch Grove Road.

More than 100 officers and volunteers were scouring the countryside while forensic experts carried out a fingertip search of the couple's luxury house.

Detectives today renewed their appeal for any walkers in the vicinity of the Horsted Keynes ponds on the afternoon of Sunday, December 12, to contact them.

They also want to trace the owner of a dark grey car seen in the car park close to the Ashdown Cricket Club, off Birch Grove Road, on Monday.

A force spokeswoman said: "We would urge the owner or any dog walker who may have seen the car to come forward and help detectives with their inquiries."

Mrs Ball, who works in school insurance for the HSBC bank in Haywards Heath, left their converted barn on Monday last week. Work colleagues raised the alarm when she failed to show up.

Her disappearance is the talk of the normally quiet village, which nestles in countryside close to the famous Bluebell Line preserved railway at nearby Sheffield Park.

The last friend to speak to Mrs Ball was neighbour Bill Wood, a 72-year-old widower.

He said: "She is a very nice, friendly woman, very smiley, happy and charming. I've no idea what has happened to her. The whole thing seems very strange.

"I'm very upset about it. Hilary is a very good friend of mine."

Mrs Ball phoned him two days before she disappeared.

He said: "I go to the Green Man pub down the road with Hilary and Geoff.

"We met in there and got chatting about six years ago. She is a very nice woman, very friendly.

"We go to the pub every Friday and Saturday night. Geoff plays a lot of bridge while Hilary and I chat.

"I've been invited to eat at their house three times and they've always been very hospitable.

"Hilary always rings me Friday nights to see if we are going down the pub but the weekend before she disappeared she called on the Saturday evening.

"That was unusual. I was watching football on the telly when the phone rang.

"It had been a nice day and we spoke about the weather. She'd been out in the garden all day working and I'd been to visit my wife's grave.

"Hilary sounded perfectly normal but said she wasn't coming down to the pub. She said she was sitting by the fire.

"It was slightly unusual she didn't come out but she was a bit tired.

"We chatted a bit more about my children - she likes talking about them a lot - but that was it. I was the last friend to talk to her before she disappeared."

Mr Wood, a retired water board superintendent who was widowed six years ago, said Mr and Mrs Ball seemed a devoted couple.

He said: "Geoff has been down to see me a couple of times since she disappeared.

"They're good company, the pair of them. I always look forward to seeing them and I miss Hilary terribly."

Villagers have been searching back yards and fields. The couple's house, opposite a retirement home, is surrounded by open farmland.

Neighbour Peggy Body lives a half-mile along the road and said: "Police keep coming round to my house and asking for ideas where Mrs Ball might be but it is an absolute mystery."

Mr and Mrs Ball have been together since 1979 and were married in 1985.

Mr Ball took part in a Press conference at Horsham police station on Monday and pleaded for help to find his wife.

Her disappearance, he said, was completely out of character: "No one seems to know where she has gone. We're mystified."

Mr Ball described his wife as "well-loved" and added: "She is a very private person and also a very strong character."

He said nothing untoward had happened when she left their home to go to work last week.

Her blue Toyota Yaris car, GX51 LXZ, was discovered on a path from Birch Grove Road, close to the cricket club pavilion being used as a headquarters for the police search teams.

Police appealed to anyone who may have seen Mrs Ball's car from Saturday to Monday of last week to come forward.

The huge police search has included land around Birch Grove House, Chelwood Gate, former home of the late prime minister Harold Macmillan.

Mrs Ball is 5ft 4in, slim and was wearing a stone-coloured Berghaus jacket with khaki shoulder patches and a terracotta collar.

Police asked anyone with information to contact the Operation Elphin incident room on 0845 6070 999.