Masked men have broken on to the set of a TV channel in Ecuador waving guns and explosives during a live broadcast, and the president issued a decree declaring that the country had entered an “internal armed conflict”.

The men armed with pistols and what looked like sticks of dynamite entered the set of the TC Television network in the port city of Guayaquil and shouted that they had bombs. Noises similar to gunshots could be heard in the background. It was not immediately clear if any station personnel were injured.

Alina Manrique, the head of news for TC Television, said she was in the control room across from the studio when the masked men entered the building. One of the men pointed a gun at her head and told her to get on the floor, she said.

Some of the assailants ran from the studio and tried to hide elsewhere in the building when they realised they were surrounded by police, she added.

“I am still in shock,” Ms Manrique told the Associated Press in a phone interview. “Everything has collapsed. All I know is that its time to leave this country, and go very far away.”

Ecuador has been rocked by a series of attacks, including the abductions of several police officers, after a powerful gang leader’s apparent escape from prison on Sunday.

President Daniel Noboa said on Monday that he would declare a national state of emergency, a measure that lets authorities suspend people’s rights and mobilise the military in places like prisons.

Shortly after the gunmen stormed the TV station, he issued another decree designating 20 drug trafficking gangs operating in the country as terrorist groups and authorising Ecuador’s military to “neutralise” the groups – within the bounds of international humanitarian law.

Ecuador’s national police chief announced a short time later that authorities had arrested all the masked intruders. Cesar Zapata told the TV channel Teleamazonas that officers had seized the guns and explosives. He said 13 people were arrested.

“This is an act that should be considered as a terrorist act,” Mr Zapata added.

The government has not said how many attacks had taken place since it announced that Los Choneros gang leader Adolfo Macias, alias “Fito”, had gone missing from his cell in a low security prison on Sunday. He had been scheduled to be transferred to a maximum security facility that day.

Authorities have also not said who is thought to be behind the attacks, which included an explosion near the house of the president of the National Justice Court and the Monday night kidnappings of four police officers, or whether they think the actions were co-ordinated.

Police said one officer was abducted in the capital Quito and three in Quevedo city.

The government has previously blamed members of the main drug gangs for similar strikes. In recent years, Ecuador has been engulfed by a surge of violence tied to drug trafficking, including homicides and kidnappings.

Macias’s whereabouts are unknown. Prosecutors opened an investigation and charged two guards in connection with his alleged escape, but neither the police, the corrections system, nor the federal government confirmed whether the prisoner fled the facility or might be hiding in it.

In February 2013, he escaped from a maximum security facility but was recaptured weeks later.

On Monday, Mr Noboa decreed a national state of emergency for 60 days, allowing the authorities to suspend rights and mobilise the military in places like prisons. The government also imposed a curfew from 11pm to 5am.

Mr Noboa said in a message on Instagram that he would not stop until he “brings back peace to all Ecuadorians”, and that his government had decided to confront crime. The wave of attacks began a few hours after his announcement.

States of emergency were widely used by Mr Noboa’s predecessor, Guillermo Lasso, as a way to confront the wave of violence that has affected the country.

Macias, who was convicted of drug trafficking, murder and organised crime, was serving a 34-year sentence in La Regional prison in the port of Guayaquil.

Los Choneros is one of the Ecuadorian gangs authorities consider responsible for a spike in violence that reached a new level last year with the assassination of presidential candidate Fernando Villavicencio.

The gang has links with Mexico’s Sinaloa cartel, according to authorities.

Experts and authorities have acknowledged that gang members practically rule from inside the prisons, and Macias was believed to have continued controlling his group from within the detention facility.