A court has heard how a Brighouse father and son chased after two would-be burglars after they were seen acting suspiciously outside a large detached home.
Christopher Wallace had spotted the two men near to the property when he was putting out some recycling last October and his son Timothy later saw the two suspects in the rear garden looking through the windows of the conservatory at about 8pm.
Prosecutor Philip Adams told Bradford Crown Court that Mr Wallace senior shouted at the two men who ran off, but the father and son then chased after them.
Timothy Wallace managed to grab hold of Scott Connor and during a struggle a knife fell to the ground.
"The defendant was detained by the witnesses and others until the police arrived and he arrested.
Connor, 38, of Whinney Hill Park, Brighouse, later handed over a bag containing three homemade face coverings cut from a tee-shirt together with a torch and some gloves.
Connor claimed that he had been given the bag by the other man who he had only known for a couple of hours.
During a discussion about the case the Recorder of Bradford Judge Jonathan Durham QC described Timothy Wallace as "a very brave young man" and added:"We know the consequences of tackling criminals can be extreme."
Barrister Glenn Parsons, for Connor, said there was no suggestion that the knife had been produced or used aggressively by his client and he hoped to persuade the judge to suspend any prison term.
He explained that Connor had been "sofa surfing" and living rough at the time and had only been carrying the knife for his own protection.
Connor pleaded guilty to charges of going equipped for burglary or theft in respect of the items in the bag and a further offence of having an article ex with a blade or point in relation to the kitchen knife.
Judge Durham Hall said the case involved some "worrying traits", but he needed a full report from the probation service.
Connor, who is subject to a night-time curfew, was granted bail until his sentence hearing on April 26.
"This is very, very serious for obvious reasons," the judge told Connor.