Il Nuovo Postiglione - 20 dead in Argentina after taking toxic cocaine

Officials said they were working quickly to determine what the cocaine was mixed with and "remove it from circulation", warning those who bought the drug over the last 24 hours to dispose of it.

Buenos Aires provincial security chief Sergio Berni described the additive as "a key ingredient that is attacking the central nervous system" while speaking to television channel Telefe.

Beatriz Mercado told AFP she had found her 31-year-old son, one of the victims, lying face-down on the kitchen floor.

"He was almost not breathing, his eyes were rolling back," she said. She took him to the hospital, where he was on life support as of Wednesday evening.

"I hope in God, nothing else. A miracle."

About 10 people were arrested after police raided a house in the poor Tres de Febrero neighborhood where they believe the cocaine was sold and packets of the substance similar to those described by the victims' families were seized.

The drugs were taken to a laboratory in La Plata, the capital of Buenos Aires province, for analysis.

Authorities issued an urgent warning early Wednesday after three separate hospitals reported several deaths and serious cases of poisoning.

Several of those being treated told doctors they had taken cocaine together.

An initial toll of 12 deaths and 50 hospitalizations kept rising -- with victims admitted to eight different hospitals, a Buenos Aires province government spokesperson told AFP.

Earlier reports said the victims suffered convulsions and sudden heart attacks.

Health authorities said at least four of the victims were men aged between 32 and 45.

"We are desperate, we want to know why one person is dying after another here," said Maria Morales, outside the hospital where her brother-in-law was being treated.

Berni's office said late in the day that emergency services were reporting new patients in "critical condition" being brought to hospitals.

- Cut with harmful substance -

"Every dealer that buys cocaine cuts it. Some do it with non-toxic substances such as starch. Others put hallucinogens in it, and if there is no form of control, this kind of thing happens," Berni said.

But on this occasion the drug was cut with a harmful substance as part of a "war between drug traffickers," he added.

But San Martin public prosecutor, Marcelo Lapargo, said the idea of a battle between drug traffickers was "conjecture" at this point.

Lapargo told Radio Mitre that authorities' main concern "is to be able to communicate so that those who are in possession of this poison know that they should not consume it."

Investigators fear the toll could rise, with some people who bought the cocaine unable to reach a care center in time.

Lapargo said that this case was "absolutely exceptional".

Police clashed briefly with residents in a part of Tres de Febrero who were protesting the arrest of local young people in the drug raid.

S.Urgo--INP