Four children and two adults have been injured in a knife attack in the Alpine town of Annecy in France. The children – one aged 22 months, two aged two years old and one aged three – were in a critical condition from stab wounds, and were transferred to hospitals in the French Alps and across the Swiss border in Geneva on Thursday afternoon. Dozens of other very young children were receiving support for the trauma of witnessing the stabbings, which happened at a lakeside playground. High school children who also witnessed the attack were being treated for shock. One of the critically injured young children was British, the UK foreign secretary, James Cleverly, confirmed. French authorities said the British child was a tourist. Another of the children was Dutch. A 70-year-old man was also seriously injured – first stabbed by the knife-attacker and then injured by police fire. A second adult was treated for injuries. At about 9.45am, a man armed with a knife entered the playground near Annecy’s famous lake, an area prized by locals and tourists for its quiet calm and breathtaking views. The man walked past the adults in the park and targeted very young children with a knife – including one child in a pushchair, according to witnesses. Within minutes, the attacker was pursued by police. He then attacked an elderly man in a different part of the park. Police fired shots and detained the attacker, who was unharmed, and was being questioned by police. The local prosecutor said an inquiry was under way for attempted murder. National police, rather than anti-terrorist investigators, are heading the investigation. The prosecutor said the initial investigations showed that “there is no apparent terrorist motive”. The French prime minister, Élisabeth Borne, said the suspect was a Syrian man who had been granted refugee status in Sweden. Police described him as aged in his early 30s. Borne said he was homeless and an “isolated individual”. He had asked for asylum in France, which had not been processed because he already had refugee status in Sweden. Because he had EU refugee status, he was free to travel legally to France. Police sources told Le Monde that the man had declared himself to be a Syrian Christian in his French asylum application. Le Monde and other French media reported that he had been wearing a Christian cross on a chain round his neck when arrested. Borne said French authorities had contacted international security and intelligence agencies and the man was unknown to any French, European or other foreign security service. He had no criminal record, and no apparent psychiatric record, she said. Borne described the attack as “savage” and said the whole of France had been “shaken by this hateful, indescribable act”. The French president, Emmanuel Macron, tweeted that it was an act of “absolute cowardice” and that the nation was in shock. Cleverly, who was speaking at an Organisation for Economic Co-operation and Development ministerial council press conference in France, called the attacks a “terrible act of violence” and said the British government was ready to support the French authorities in whatever way it could. The former Liverpool footballer Anthony Le Tallec, who has also played for FC Annecy, was out running near the lake at the time of the attack. He described suddenly seeing dozens of people running towards him, a mother shouting: “Run, someone is stabbing everyone, he’s stabbing children!” Le Tallec, 38, said on Instagram and in later French media interviews that he was surprised but kept running, then saw the attacker running followed by police chasing him, trying to catch him. Le Tallec said he saw the attacker then rush towards a group of elderly people where he stabbed a man twice. Le Tallec said he had shouted at the police to shoot the man. Another witness, Malo, told BFMTV that the man was “shouting, but it wasn’t really comprehensible”. Another witness told local public radio that the attacker had seemed “confused”. A witness called Nelly told France Info radio: “People were running, crying, panicking … it was horrible.” The prime minister travelled to the scene alongside the interior minister, Gérald Darmanin. MPs in the national parliament held a minute’s silence as news of the attack broke in the French media. Some politicians on the right and far right called for more scrutiny of France’s immigration and asylum policy, seizing on the suspected attacker’s identity as a refugee. “The investigation will determine what happened, but it seems like the culprit has the same profile that you see often in these attacks,” the head of the rightwing Républicains party, Éric Ciotti, told reporters at parliament. “We need to draw conclusions without being naive, with strength and with a clear mind.” Jordan Bardella, the head of Marine Le Pen’s far-right National Rally party, the biggest single opposition party in parliament, tweeted that French immigration policy and European rules should be reviewed. Asked for her view on politicians who responded to the attack by saying France should tighten its immigration policy, Borne said all light should be shed on the investigation but that today was the “time for emotion” and she was in Annecy to express the support and solidarity of the nation.