The teenager, who is suspected to be a minor, had been working at the victim's residence as a domestic help for the past seven days. He hails from Jharkhand and was hired through a placement agency and police are presently verifying his papers, DCP (Central) Parmaditya said today.
Around 8 PM yesterday, a 68-year-old woman, identified as Shanti Chopra, was found dead inside her residence. She was allegedly beaten to death with a wooden laundry bat, which has been recovered by the police.
The accused had also allegedly thrashed Chopra's elder son when he tried to stop him.
Police suspected the teenager when he was found missing. They also discovered that the woman had been robbed of cash and other valuable belongings.
Four police teams were formed and the accused, who had also allegedly taken away Chopra's mobile phone, was tracked near New Delhi Railway Station.
The accused was found sitting in Magadh Express and apprehended at Etawah. The police also recovered around Rs 3.70 lakh, Chopra's mobile phone and the weapon of offence from his possession.