DHAKA: Bangladesh Monday ended its confinement of opposition leader Khaleda Zia after a surge in political violence left 27 people dead, but her party vowed to continue a nationwide transport blockade.

Zia had been barred from leaving her office for the last 16 days to prevent her from spearheading protests aimed at toppling her arch-rival, Prime Minister Sheikh Hasina.

Police stationed outside Zia's office in Dhaka's upmarket Gulshan district were stood down Monday, while two police vans and a water cannon parked outside were removed.

“We've withdrawn the additional security from her office after midnight, “local police chief Rafiqul Islam told AFP, adding that the former two-time premier was now free to leave.

Read: Bangladesh showdown as opposition leader locked in office

The siege at her office sparked a renewed upsurge in political unrest around the country that left 27 people dead and hundreds injured.

Zia's opposition Bangladesh Nationalist Party (BNP) confirmed the security had been removed but vowed Monday to push ahead with the transport blockade which she called during her confinement.

The blockade has seen opposition activists firebomb buses, cars and lorries across the country, while police have retaliated by firing bullets and tear gas.

Also read: Bangladesh court bans reporting of opposition chief's son

“The BNP-led 20-party opposition alliance's transport blockade will continue until the government agrees to our demand,” said party spokesman Sayrul Kabir Khan.

“At the moment, there is no security outside her office,” Khan added.

The blockade has hit the impoverished nation's economy hard, with shipments of garments from its thousands of factories disrupted. Bangladesh is the world's second largest garment exporter after China.

Transport operators estimate they are losing $26 million a day, while millions of dollars worth of crops have rotted in the fields.

A total of 238 vehicles have been torched since January 4 and another 307 damaged, according to Bengali daily Prothom Alo.

Demand for fresh polls

Zia wants Hasina to call fresh polls after last year's controversial general election, which was boycotted by opposition parties on the grounds it would be rigged and was marred by deadly violence.

The boycott meant most members of the 300-seat parliament were returned unopposed, handing Hasina another five years in power.

Also read: Deputy chief of Khaleda’s party held

Zia has also demanded the release of opposition officials and leaders detained in a crackdown against the latest violence. The BNP says at least 2,000 of its activists have been arrested.

On Monday police arrested Nadim Mostofa, a BNP leader in the northwestern city of Rajshahi.

As part of the crackdown, authorities have blocked smartphone messaging services Viber and Tango to prevent protesters from coordinating attacks.

Also read: Khaleda Zia faces murder charge threat

Hasina has accused bitter rival Zia of trying to trigger “anarchy” and ordered the security agencies to hunt down the protesters behind the firebombings.

Facing relentless opposition protests, Hasina's government has also threatened to bring murder charges against Zia for inciting violence.

Hasina and Zia, who have between them ruled Bangladesh for most of the last three decades, have a notoriously poisonous relationship.

The United States, Britain and the European Union have expressed concern over the unrest.

The EU, the nation's biggest export destination, has urged Hasina's government and the opposition to hold talks to resolve the crisis.