Anshul, Kuldeep and Sushil Kumar were arrested by the Crime Branch of Delhi police.
A country-made pistol and two live cartridges along with a car were recovered from them, according to police.
"We got a tip-off that three inter-state carjackers who were involved in carjacking at gunpoint would be coming near Najafgarh-Bijwasn road. A trap was laid near BSF camp and the trio was nabbed," Additional Commissioner of Police (Crime) Ravindera Yadav.
"In one of the incidents, the trio used two school going kids. The minors hired a car from Koshi in Haryana to Baghot.
"This gang used minors to commit crimes with a view to conceal their identity. The taxi drivers readily agreed to ferry minors to any destination without asking for any surety and identity," said Yadav.