KATHMANDU, Sept 9 (Reuters): Nepali Prime Minister K.P. Sharma Oli was forced to resign on Tuesday by angry young anti-corruption protesters who defied a curfew and clashed with police a day after 19 people died in a first day of protests.

The outrage was sparked by a social media ban, which Oli's government lifted after police fired tear gas and rubber bullets at protesters trying to storm parliament, and 100 people were injured alongside the 19 dead.

But there was no let-up in the protests on Tuesday, which plunged Nepal into fresh political uncertainty.

The unrest is the worst in decades in the poor Himalayan country, which is wedged between India and China and has struggled with political and economic instability since protests led to the abolition of its monarchy in 2008.

Young Nepalis have for years been frustrated at the lack of jobs, and millions have gone to work in the Middle East, South Korea and Malaysia, mainly on construction sites, from where they send money home.

"In view of the adverse situation in the country, I have resigned effective today to facilitate the solution to the problem and to help resolve it politically in accordance with the constitution," Oli said in his resignation letter to President Ramchandra Paudel.

An aide to Paudel told Reuters the president had begun the process of finding a new premier, but also summoned protest leaders for talks.

Army chief Ashok Raj Sigdel, in a video address, urged the protesters to end the unrest and avoid further loss of life and property, and come for talks.

In a separate statement the army said it was firmly committed to protecting people's lives and property.

The U.S. urged all sides to refrain from violence.

A State Department spokesperson said the U.S. remained a "steadfast partner of Nepal, committed to our shared interests in stability, prosperity, and democratic governance".

Jubilant youths entered the parliament complex on hearing that Oli had resigned, waving their hands and shouting slogans as smoke rose from sections of the building.

"We won," one wrote in huge orange letters on the wall of the parliament building.

Although many protesters remained on the streets, there was no more violence as security forces kept their distance.

Photo from Reuters