20 July 2012 Last updated at 04:23 ET

Javaid Ali Paisley murder police report 'encouraging leads'

Mr Ali died in hospital after being stabbed in his shop in Paisley

Police investigating the murder of a Renfrewshire shopkeeper have said there was a good response to the BBC's Crimewatch programme.

Javaid Ali, 48, was stabbed in Sunshine Grocers, Paisley, on 15 June. He died in hospital on 29 June.

On Thursday's edition of Crimewatch, Strathclyde Police made a fresh appeal for help to trace his killer.

A reward of £50,000 has been offered for information leading to the arrest of the person responsible.

Det Ch Insp Duncan Sloan revealed that two calls were of particular interest.

He said: "The first is from a male who says he knows information and was going to to attend at Paisley police office.

"This is really encouraging and I would welcome this but I would ask him to please call back so we can speak to him."

Det Ch Insp Sloan also gave details of a caller who had named a suspect.

He added: "We had a call from an anonymous male who named an individual responsible and stated that he'd seen a weapon that had been used.

"Clearly this is important and I would urge that caller to please call back.

"I'll be sitting waiting for that phone call."

Two weeks ago, Abbas Ali, 25, one of Mr Ali's three sons, issued a statement appealing for help.

'Trauma and hurt'

He urged anyone with information to "think of the trauma and hurt" caused to his family and contact police.

The statement read by Mr Ali said: "Our family is absolutely devastated at the loss of my father, Javaid Ali. He was a wonderful father, husband, son and friend.

"He meant so much to us and it is heartbreaking to know we will never see or speak to him again.

The attack took place at the Sunshine Licensed Grocers in Paisley on 15 June

"I cannot put into words the suffering this has caused our family and it will take a long time for us to come to terms with what has happened."

Mr Ali said he could not have asked for more from his father whom he described as "an exceptionally hard worker and a great provider for our family".

"He always put our needs first and did his best to provide my brothers and I with opportunities that he did not have when he was younger," he said.

More than 60 officers are working on the inquiry and have visited 700 homes and taken up to 170 statements so far.

Detectives are still trying to trace a man who was seen walking from the direction of Sunshine Grocers at about 15:00 on the day Mr Ali was attacked, and a young woman carrying Aldi shopping bags.

She was walking towards Green Road in the direction of the cycle track.