Hindu hardliners blocked intersections, threatened drivers and ordered a 12-hour strike on Thursday as they stepped up their campaign to bar women from one of India's holiest temples.

The Lord Ayyappa temple at Sabarimala in the southern state of Kerala was meant to allow women from Wednesday following an order last month by India's highest court.

But hundreds of traditionalists, throwing stones at baton-wielding police, defied the order — surrounding and shouting at any woman attempting to make it to the hilltop site.

Angry young men also surrounded and smashed the car windows of female television reporters and threatened others, including an AFP reporter. Another female correspondent was kicked.

Overnight local Hindu groups declared a 12-hour shutdown of local businesses, telling drivers that their vehicles would be attacked if they took anyone towards the temple.

"Some men came to the parking lot early Thursday and warned taxi drivers against defying the shutdown call," taxi driver Praveen, in the town of Pathanamthitta, told AFP.

"They warned drivers at several nearby parking lots and hotels. Anyone who defies it will be risking damage to his vehicle," he added in an account corroborated by other drivers.

"No one will get to the temple today because all the drivers are scared for the safety of their cars," one hotel receptionist told AFP.

State authorities have insisted that they will ensure access to the temple, imposing restrictions on public gatherings that came into force from midnight.

Kerala police, who have drafted in hundreds of extra officers, many with helmets and body armour over their khaki uniforms, provided escorts to some buses.

Police also patrolled through the night and reinforced their presence at Nilackal, the base camp below the temple.

But groups of between 50 and 100 young men gathered at intersections on Thursday, preventing any vehicles from continuing towards the temple.

"Traditions that have existed since before courts cannot be tampered with," said Krishna Kumar, a tall muscular man in his twenties at one crossroads in the town of Kozhencherry.

##'Impure'

Last month India's Supreme Court overturned a ban on females of menstruating age — judged between 10 and 50 years — entering and praying at the hilltop temple, reached by a tough uphill trek.

Women are permitted to enter most Hindu temples but female devotees are still barred from some.

The entry of women at Sabarimala was long taboo but a ban was formalised by the Kerala High Court in 1991, a ruling overturned by India's Supreme Court last month.

The restriction reflected an old but still prevalent belief among many that menstruating women are impure and the fact that the deity Ayyappa was reputed to have been celibate.

The Supreme Court ruling enraged traditionalists, including supporters of Prime Minister Narendra Modi's nationalist Bharatiya Janata Party (BJP).

Biju S. Pillai, a local man in his thirties, was one of those opposed to the court ruling, telling AFP that he returned from working in Dubai to "protect the sanctity of the temple".

"No one should be able to change the way this temple has functioned for centuries," he said. "If any change is made they will have to kill us and go over our bodies".

EP Jayarajan, a minister in the Kerala government, blamed the violence on "goons" from the Rashtriya Swayamsevak Sangh (RSS), a hardline Hindu group seen as close to Modi's BJP.

The head of the BJP in Kerala, P.S Sreedharan Pillai, told AFP on Wednesday that their party advocated "peaceful protest against the court verdict".

"The overwhelming majority of women oppose the Supreme Court ruling,” he added.