Updated 13.30

A teenager, who can't be named because of his age, has appeared in court charged with the carjacking of a taxi near Terenure in Dublin.

It's the third such crime to take place in Dublin in the past week alone and Gardai are asking drivers to be extra vigilant.

At around 5am yesterday morning, the driver picked up a fare in Tallaght and was instructed to drive towards town.

A short time later, a meat cleaver type knife was held to his throat and the passenger ordered him to hand over all his money.

His iPhone, iPhone charger and his coin dispenser were taken before the driver managed to escape and raise the alarm at a nearby rank.

Gardai say his attacker then drove the car through the city in a "dangerous and erratic" manner before crashing into another taxi in Cabra.

A 15-year-old boy was arrested a short time later and brought before the Children's Court this morning charged in connection with the attack.

Judge John O'Connor was told that the boy is in state care and he was granted bail on condition he stay within that secure facility and return to court in a week's time.

Cathal McMahon of the Irish Mirror spoke to Newstalk's Breakfast about these 'opportunistic crimes':  This incident was the second hijacking of a car in recent days, after a woman and her two children were carjacked on Friday. Gardaí arrested a man this morning over that incident.

Meanwhile, earlier last week a pregnant woman was hospitalised after she too became a carjack victim in Dublin's inner city.