A second person has been charged over two armed robberies and a break-in at Warrawong last month.
Shortly before midnight on Saturday, February 9, two men armed with a machete robbed a pizza delivery driver in Dean Street.
They allegedly stole money and pizzas before fleeing the scene.
The following morning, around 6.30am, an 88-year-old man and his 79-year-old wife were woken by noises in the kitchen of their Jane Avenue home.
They were allegedly confronted by two males who demanded money before punching the elderly man in the face.
The pair search a number of drawers and fled the scene with cash.
In another incident, on Saturday, February 16, a pizza-delivery man in Denise Avenue, Lake Heights was allegedly approached by two males armed with a machete around 11.50pm.
He was robbed of a money and his mobile phone.
Strike Force Lynista, comprising detectives from Lake Illawarra Local Area Command, was formed to investigate the incidents.
Detectives yesterday arrested an 18-year-old man in Warrawong.
He was taken to Lake Illawarra police station and charged with aggravated break, enter and commit serious indictable offence and two counts of robbery in company. He was refused bail to appeal in Wollongong Local Court today.
Earlier in the week, detectives arrested and charged a 13-year-old boy over his alleged involvement in the incidents. His matters are before the courts.