A toddler and a five-year-old girl were raped in separate attacks in New Delhi overnight with at least one gang-raped, police said Saturday, as activists warned of an "epidemic" of sexual violence in the capital.

The two-and-a-half-year-old girl was abducted from a religious event in west Delhi by two men on Friday night and raped before being dumped in a park near her home.

In a separate incident on the other side of the city, the five-year-old was lured to a neighbour's house
and raped by three men, a police officer told AFP.

The two attacks come as New Delhi grapples with a grim litany of sexual attacks against women -- and in several recent cases, children -- that have sparked outrage in India and abroad.

"We have launched a manhunt for the suspects. So far no one has been arrested," Pushpendra Kumar, West Delhi police chief, told AFP of the younger girl's case. 

Two men were involved in the abduction of the girl and the tests have confirmed rape," Kumar said, adding that further examinations would show whether both men raped the toddler.

He said they found the younger child bleeding profusely several hours after she went missing. Police have released CCTV footage of two men riding away on a motorbike with the victim in an attempt to catch the alleged perpetrators.

Police arrested three men overnight in the case of the five-year-old victim, whom tests showed was raped multiple times, after locals managed to catch her alleged assailants and hand them over to the authorities.

"Her clothes were partially torn with blood spots all over them. Some locals saw her and she told them she was sexually assaulted," an officer from Anand Vihar police station in eastern Delhi told AFP on condition of anonymity.

"Some of the locals then barged into the house and caught them (the alleged perpetrators) before handing them over to us," the officer said.

Both girls are undergoing medical treatment but are believed to be out of danger.

The latest attacks come eight days after a four-year-old girl was allegedly raped and slashed with a blade before being abandoned by a railway track in the capital. Police arrested a 25-year-old man in that attack, in which the young girl suffered severe internal injuries.