Mr Obama made an appeal for "meaningful action" against gun crime in the US shortly after the attack on Friday.
Police had also made an appeal to trace a taxi driver who may have picked up three of the suspects.
His parents and girlfriend have made an appeal for help in catching his killers on the second anniversary of his death.
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The company behind the scheme, Riverside Business Ltd, has made an appeal.
The force made an appeal on the BBC's Crimewatch programme on Thursday for sightings of a silver Toyota Hiace 300 GS van, registration CX06 ASV.
In the case of Netley in Camden, the government said it approved the application after the leader of the council made an appeal for it to do so.
The father of a Kent schoolgirl stabbed to death in an alleyway exactly 19 years ago has made an appeal from his nursing home to find her killer.
In Dunga's first meeting with journalists after arriving in South Africa, press officer Rodrigo Paiva made an appeal for journalists to avoid a "Big Brother" approach towards the team.
The family of a man who has been missing from his Edinburgh home for more than three weeks have made an appeal to anyone who knows where he is.
Earlier, Mr Tomlinson's family made an appeal for witnesses.
He made an appeal across party lines by stressing his ability to work with Democrats among lawmakers and heaping praise on the late lieutenant governor of Texas, Bob Bullock, who shepherded many of Bush's proposals through the state Senate.
They are now following up more than 25 calls received from the programme, when Dr Shakoor made an emotional appeal.
Two women whose brother was shot dead outside his home in South Lanarkshire have made an emotional appeal for help in catching his killer.
Owner Wyn Holloway says he has no more money to put in to Merthyr and the supporters club have made an urgent appeal to help keep the football club afloat.
The threat from the Gyan brothers came just a day after Asamoah, who plays his club football for Udinese in Italy's Serie A, made an emotional appeal to fans of the Black Stars over Thursday's taunts.
Mr. Obama has made an effort to appeal to business in the second half of his first term after two initial years of frayed relations.
Police have made an "urgent" appeal to anyone who saw a taxi on the day Swindon woman Sian O'Callaghan disappeared to contact them.
President Suleiman is reported to have made an 11th-hour appeal to his Syrian counterpart Bashar al-Assad to save the government from fragmenting, only to be told that he had no control over events.
The court of appeal made an exception for Mr. Haw, partly because he has been protesting so long, allowing him to continue to camp while his case is reviewed by the high court.
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An application he made in 2000 seeking permission to file an appeal even though the statute of limitations had passed was denied.
Fans of Brecon Jazz were relieved to see the festival return, after an appeal was made for a new operator to run the event.
An appeal has been made for anyone who may have seen someone suspicious in the area to contact the charity.
An appeal for information has been made after a young rabbit was found abandoned next to an electrical substation in Aberdeenshire.
An appeal for information has been made after a German Shepherd dog was found in an Aberdeen car park with a fractured pelvis.
The Court of Appeal was told the judge had made an "error of judgement" over character evidence.
Gareth Peirce, another lawyer for Mr. Assange, said the legal team hadn't made a decision yet on whether to lodge an ECHR appeal.
The Court of Appeal dismissed claims that the trial judge made an error of judgement over character evidence.
Hosting is an offering that made sense for some, but it had limited appeal overall.
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Police have made a fresh appeal about a man they want to question over an arson attack which killed eight members of a Huddersfield family 10 years ago.
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