Investigators are sifting through blast remnants and video footage at the scene of an explosion in New York City that injured 29 people.<br /><br /> FBI investigators are examining remnants of the bomb, along with another unexploded device found four blocks away.<br /><br /> A pipe bomb also exploded around 130 kilometres away in New Jersey on Saturday. <br /><br /> Examinations are underway to track any potential links.<br /><br /> What happened?<br /><br /> The explosion, on a commercial and residential street in the district of Chelsea on Saturday evening, sent a powerful shock wave through several blocks.<br /><br /> What about the injured?<br /><br /> They were all hurt by shrapnel and flying glass.<br /><br /> All 29 have been allowed home after being treated in hospital.<br /><br /> What official response has there been?<br /><br /> New York City Mayor Bill de Blasio has urged witnesses to come forward with information.<br /><br /> “It was intentional. It was a violent act. It was certainly a criminal act. It was a bombing. That’s what we know,” he told reporters.<br /><br /> He promised the security presence would be “bigger than ever” for the United Nations General Assembly.<br /><br /> The UNGA brings world leaders together in Manhattan for six days, starting on Tuesday.<br /><br /> Speaking to the media, New York Governor Andrew Cuomo said Saturday’s explosion was deliberate.<br /><br /> “At this time there is no evidence of an international terrorism connection with this incident- but it is very, very early in the investigation. Whoever placed these bombs – we will find them and they will be brought to justice.” <br /><br /> Has any group admitted planting the bombs?<br /><br /> Not so far.<br /><br /> However, New York State Governor Andrew Cuomo has described detonating a bomb in New York City as “obviously an act of terrorism”.<br /><br /> However, Cuomo resisted when reporters pressed him to give more details, saying investigators had yet to determine if there was a political motive.<br /><br /> A day of drama for the NYPD – in tweets<br /><br /> Detectives are examining CCTV footage<br /><br /> Video footage is still being gathered and reviewed by detectives. pic.twitter.com/h2gszIvrP6— NYPD NEWS (@NYPDnews) September 18, 2016<br /><br /> W23 st device being examined<br /><br /> The specific design/components of the device that exploded on W23St is being investigated. pic.twitter.com/DLjOnrwzbm— NYPD NEWS (@NYPDnews) September 18, 2016<br /><br /> Police troopers found device<br /><br /> The device on W27St was initially found by responding NYS Police troopers. pic.twitter.com/KBbNKj3cUT— NYPD NEWS (@NYPDnews) September 18, 2016<br /><br /> All buildings in the area are structurally sound<br /><br /> The buildings in the area were checked by FDNY & NYCBuildings and deemed to be structurally stable.— NYPD NEWS (@NYPDnews) September 18, 2016<br /><br /> Two active crime scenes<br /><br /> There are two active crime scenes: West 23 Street and West 27 Street. The device that exploded on W23St was done intentionally.— NYPD NEWS (@NYPDnews) September 18, 2016<br /><br /> All 29 injured have now left hospital<br /><br /> All 29 people injured last evening in the Chelsea explosion have been released from the hospital. pic.twitter.com/cEWdtW
