Quito, Feb 13 (IANS/EFE): At least 18 inmates escaped from a maximum-security prison in the coastal city of Guayaquil, Ecuadorian authorities said.

The Justice Ministry said on Twitter that the escape from the penitentiary known as La Roca "is being investigated".

"There are no dead or wounded in the jailbreak...," the ministry said, though several media outlets have warned that the number is likely to be between 18 and 20.

The ministry denied that drug trafficker Oscar Caranqui was among the escaped convicts, but said that at the moment inmates with ties to the criminal gang called Los Choneros are being investigated.

It also said that currently underway is a joint operation of elite police and military units that have cordoned off La Roca.

At the same time, the Justice Ministry gave assurances that "security has been strengthened" at all prisons in Ecuador.

La Roca, a modern detention center that up to now has been considered the most secure in the country, holds a number of Ecuador's most dangerous criminals.