Romania's police chief has been fired over his handling of the murder of a 15-year-old girl, after it was revealed she made three emergency calls to report her own kidnapping, at one point screaming "he's coming, he's coming".

Key points: The girl was snatched on Wednesday as she tried to hitchhike home to Dobrosloveni in southern Romania

The girl was snatched on Wednesday as she tried to hitchhike home to Dobrosloveni in southern Romania She called emergency services three times on Thursday morning, but police did not execute a search warrant for 19 hours

She called emergency services three times on Thursday morning, but police did not execute a search warrant for 19 hours A 65-year-old suspect, who police believe may have killed a second teenager, was taken into custody on Saturday

Critics allege that officials failed to take the alert seriously and finally reacted too late to help save the teen, identified as Alexandra.

The girl was snatched on Wednesday (local time) as she tried to hitchhike home to Dobrosloveni in southern Romania, police said.

On Thursday morning, she managed to ring the emergency number 112 three times and provide clues to police about the place in which she was being held by a car driver who had picked her up.

The girl had yelled "he's coming, he's coming" before the phone call was cut off, authorities said.

Three buildings were searched by officers before they finally found the house where she had been held, more than 12 hours after her phone calls.

Police then sought a search warrant, which is not required in emergencies, and waited until dawn to enter the house — 19 hours after the teenager's last call.

Investigators allegedly found human remains and jewellery belonging to the girl in Gheorghe Dinca's home (pictured). ( AP: Bogdan Danescu )

A 65-year-old suspect, identified as Gheorghe Dinca, was taken into custody on Saturday (local time) after investigators searching his home and garden discovered human remains and jewellery belonging to the girl.

The suspect insisted he was innocent and had never met the teen but failed to explain why she had used his phone, his lawyer said.

Police believe a second teenager, whose parents reported her missing in the same area three months ago, may have been murdered by the same killer.

'Why did the police not intervene earlier?'

The case, which has sparked widespread protests in the capital of Bucharest, prompted Interior Minister Nicolae Moga to sack police chief Ioan Buda on Friday "because drastic measures are required".

Amid chants of "incompetence" and angry calls for the Government to step down, demonstrators placed flowers and candles at a makeshift memorial outside the Interior Ministry the following evening.

Demonstrators placed flowers and candles at a makeshift memorial in Bucharest. ( AP: Vadim Ghirda )

They have accused the ruling Social Democrats of weakening the criminal justice system with controversial reforms heavily criticised by Brussels.

"Why did the police not intervene earlier? Everyone needs to answer for this, from police officers and prosecutors to (Prime Minister Viorica) Dancila," protester Cristian Nan said.

Centre-right President Klaus Iohannis said earlier the "resignations of all those who mishandled this case which had such dramatic consequences are obligatory".

AFP/ABC