THIS is how we deal with thugs in my country, says have-a-go hero who locked up mugger of 70-year-old lady in a church By Chris Brooke Last updated at 2:20 PM on 13th August 2009 The fleeing robber was bigger than him and could have been armed, but shop assistant Amevi Kouassi didn't think twice about tackling the burly yob who attacked an old woman. 'I had to help,' he said. 'The way I was brought up in my home country of Togo, if you hear someone call for help, you have to go to their aid. It's what we are taught as children. 'It doesn't matter if you know them or don't know them. If someone is in trouble you need to help them. It is wrong to ignore them and walk away.' 'Incredibly brave': Amevi Kouassi (right) struggles to get the bag back from mugger Marc Smith in the streets of Sheffield As this dramatic CCTV footage shows, Mr Kouassi, 30, was true to his word. After hearing the 70-year-old pensioner's screams, he grabbed the man who had just mugged her in Sheffield city centre, wrestled him to the ground and locked him in a nearby church hall office while he waited for police to arrive. The mugger, Marc Smith, 37, escaped out of a fire exit, but the description given to police and CCTV evidence led to his swift arrest and conviction. Yesterday, the modest have-a-go hero was praised by police for his bravery after Smith admitted robbery and was jailed for five-and-a-half years at Sheffield Crown Court. Mr Kouassi, who is starting an information studies degree course at the University of Sheffield next month, had just left work at Marks & Spencer in Sheffield and was walking home on a June evening when he heard the woman's cries for help. 'I saw a lady on the floor and a man running. She shouted that he had got her bag so I chased after him and grabbed him,' said Mr Kouassi. Mr Kouassi holds Smith with his arms behind his back in this CCTV image. He then marched him to a church hall nearby Mr Kouassi: 'I had to help' 'You can't stand by and let something like this happen. The man had picked on a helpless old person and I didn't want him to get away. 'I managed to grab his arms, I pushed them down through his T-shirt and pinned them behind his back. 'He was shouting "you have got the wrong man", but the old lady was saying ''no you haven't''. 'I took him to a church hall nearby and a man there locked him in the office.' Mr Kouassi, from Manor Park, Sheffield, who is 5ft 9in tall and ten and-a-half stone, arrived in the UK from Togo in 2006 and has been given Home Office permission to stay for five years. He added: 'I don't consider myself to be a hero. I was just doing what I have been taught to do. 'He was taller and heavier than me but I managed to pin his arms behind his back. 'Someone said afterwards that he could have had a knife but I didn't think of that at the time.' He added that the elderly victim had sent him a thank you card. Acting Detective Chief Inspector Jade Brice, of South Yorkshire Police, said: 'It is thanks to Mr Kouassi's brave actions that we have been able to arrest and convict the offender. 'He put himself in harm's way in what was an incredibly brave action.'