The Samajwadi Party's Abu Azmi was hit by legislators from a regional party who wanted him to take the oath in the local language, Marathi.

The four assailants have been suspended from the assembly for four years.

The Maharashtra Navnirman Sena party has been campaigning for greater rights for the Marathi people of Maharashtra.

The party has been accused of several attacks on migrant workers in the past couple of years.

The MNS is led by Raj Thackeray - a nephew of Bal Thackeray, the founder of the right-wing Hindu Shiv Sena party.

Slapped

The MNS legislators attacked Mr Azmi on Monday as soon as he began taking the oath in Hindi.

They snatched the microphone and one MNS member, Ram Kadam, slapped him.

Later, the assembly passed a resolution suspending the four legislators - Vasant Gite, Shishir Shinde, Ram Kadam and Ramesh Wanjale - for four years for unruly behaviour.

Politicians from various parties have condemned the assault.

India's governing Congress Party has described the incident as "constitutionally impermissible and democratically shameful".

The assembly began a three-day special session on Monday for newly-elected legislators to take their oaths.

Assembly elections were held in Maharashtra last month and the Congress and its regional ally Nationalist Congress Party secured a comfortable win.

Maharashtra is one of India's most important states. Its capital, Mumbai (Bombay), is the country's financial centre. The Congress has ruled the state for the last two terms with its ally the NCP.

Mr Azmi accused the MNS members of double standards.

"The very same MNS people who are spreading hatred, resort to Hindi during elections as they go about asking for votes in Maharashtra. Their CDs, pamphlets, all are in Hindi," he said.

"For seeking votes, Hindi is good, but they raise objections if some official work like oath-taking is held in the Hindi language.

"Yesterday it was proved that they have nothing against English. If somebody takes the oath in English in the Maharashtra assembly, they will have no objection, but if anybody takes the oath in Hindi, the official language, they will be manhandled."