[Pantyholic]

JEREMY MCDERMOTT

MEXICAN police have set up a task force of 100 detectives to find the "Mataviejitas", or Little Old Lady Killer, who is believed to be responsible for the murders of at least 32 elderly women in Mexico City.

The most recent victim, María Reper Hernández, 92, was found this week strangled with a scarf and brutally beaten.

The authorities admit that the suspected cross-dressing serial killer has so far outwitted them. "It's a criminal who acts alone, takes a lot of care and has brilliant intelligence," said Mexico City's attorney general, Bernardo Bátiz. "He or she acts with a lot of skill, gaining the trust of the victims and leaving few clues."

The police are being cautious in releasing what evidence they have, but have shown two artist's impressions of the suspect, one as a man, the other as a woman.

A masculine-looking woman, about 5ft 6in and of stocky build, has been linked to several of the crime scenes by witnesses, including one woman, who survived an attack but whose identity has been kept secret.

It is known that a set of fingerprints was lifted from one of the crime scenes.

Using FBI profiling techniques, the Mexican authorities have sought to build up a psychological portrait of the killer. Experts have been called in, such as criminologist Miguel Ontiveros, who said: "It was likely there was abuse, perhaps sexual abuse, committed by a mother or grandmother. He kills with his bare hands, always through strangulation or beating."

The task force has broken down Mataviejitas's method into four phases: the identification of the victim who almost always lives alone; the "seduction", when the old woman's trust is won; the murder; and finally the collection of a trophy.

"We know it is a serial killer, as he takes totemic items, like rings or statues, from victims' homes as trophies," said Mr Ontiveros.

Detectives are now analysing each murder using the four phases and seeking to warn Mexico City's elderly community of the risks by distributing 500,000 leaflets about the killer.

"The elderly need to be more cautious and not open their doors to people they don't know, or who come up to them in the market offering to take them home or help them," said Laura Perez, spokeswoman for the National Institute for the Elderly.

Detectives have so far focused their search on Mexico City's transvestite population, trawling red light districts for transvestite prostitutes and taking fingerprints.

Three of the last four victims had one thing in common. All had a reproduction of the 18th- century painting Boy in Red Waistcoat, by Jean Baptiste Greuze, on their walls depicting a cherubic boy with a slightly fearful expression on his face.

"It's no coincidence they all had this portrait," said Mr Ontiveros. "We think the feminine boy figure in the painting could point to a killer with a sexual identity crisis."