Thiruvananthapuram, June 16: A migrant worker from Assam has been arrested for the rape and murder of a law student in Kerala, which paralleled the Delhi bus gang rape in its brutality and became an election issue in the southern state.

Television channels identified the accused as Amyur Ul Islam. Sources said he was picked up from the border of Palakkad district in the state's north and had confessed to the crime. However, PTI reported that he was arrested from Kanchipuram in Tamil Nadu.

Chief minister Pinarayi Vijayan said the police had been tracking the suspect since yesterday and added that the arrest was a "feather in their cap". "The people of Kerala were waiting for such news," PTI quoted him as saying.

The 29-year-old student was raped and murdered on April 28 in her home, a one-room shanty, in Perumbavoor near Ernakulam where she lived with her mother. Her body was found covered with deep wounds.

With the crime coming to light just ahead of the Assembly elections, the Left which was then in the Opposition used it to target chief minister Oommen Chandy. The dead girl's mother criticised the local MLA, Saju Paul of the CPM, who she claimed had turned down their repeated pleas for help to construct a safer house. Paul lost this election although the Left came to power in the state.

One of the first decisions of the new government, which assumed office last month, was to hand over the investigation to a woman additional director general of police. A drop box was put up in Perumbavoor for anyone wishing to share information on the assault with the police while remaining anonymous.

The additional director general of police, B. Sandhya, confirmed there had been an arrest but refused to give details. "We have got the accused. The next step is to do the needful to prosecute him," she said.

Sources said the 23-year-old accused also lived in Perumbavoor and knew the law student. He was upset with her because she had laughed at him a day before the murder when a group of women heckled him as he landed at a ladies' bathing ghat 200 metres from where she lived. The next evening, he arrived at her home and a war of words followed. Sources said he was drunk at the time.

PTI reported that the police had secured CCTV footage from a shop in the victim's neighbourhood, which showed the suspect following the law student hours before the crime.

After the murder, the accused returned to Assam and dumped his SIM card on the way, the sources said. He later got a job in Tamil Nadu and while on the way there, purchased a new SIM for his old phone. As the instrument came alive, it alerted the police's cyber cell which had traced the IMEI number and was watching its movements, the sources said.

Sources said a pair of sandals found near the victim's home had led the police to the shop from where the suspect had bought them. A photo studio owner had also identified Islam, saying he had once accompanied the victim to his studio, the sources said.

Perumbavoor, which has a number of plywood factories, is home to a large number of migrant workers.