NEW DELHI: The head of India's ruling party was acquitted of three murder charges on Tuesday in a trial that had undermined the government's promise to usher in a new era of clean politics.

Shah, the closest aide of Prime Minister Narendra Modi, was cleared of ordering police to carry out the extrajudicial killings of a gangster — Sohrabuddin Sheikh, his wife and his friend — when he served as home minister under Modi in the state of Gujarat almost a decade ago, Shah's lawyer, Mitesh Amin, said.

Amin said Shah was acquitted due to lack of evidence and the judge would give a more detailed explanation after a recess.

Shah was promoted to president of the Bharatiya Janata Party in July as he awaited his trial, two months after helping Modi deliver India's biggest election victory since 1984.

Party workers praise Shah as an efficient administrator, whose sharp political mind has helped him win nearly every election he has overseen in the last three decades.

Rubabuddin Sheikh, the brother of one of the victims, said his family would challenge the ruling.

“Amit Shah has wrongly been protected and we will challenge the court's order in the high court,” Sheikh said.

India's top law enforcement agency, the Central Bureau of Investigation (CBI), had accused Shah of running an extortion racket with police officers and Sheikh while holding the top law-and-order position in Gujarat.

Shah and Sheikh fell out and police snatched Sheikh from a bus with his wife in 2005, the CBI said in a charge sheet.

Sheikh was killed in a staged gun battle and his wife's cremated body was later found in the village of one of the policemen, the CBI report said.

Phone records show Shah had multiple calls with the accused officers during the operation and was “pivotal” to the conspiracy, the police said in the report.

A year later, a friend of the couple who witnessed the abduction was killed in a shootout with police.

The Gujarat government later admitted all three murders were staged, according to court documents. Police officers remain on trial for the killings.