With only days to go until Formula 1 drivers compete for pole position at Sunday's (April 21) Bahrain Grand Prix, the race has once again sparked controversy in the Gulf island kingdom.

Bahraini authorities said on Monday (April 15) they would step up security before hosting the event after a series of explosions, including a gas cylinder blast that set a car ablaze in the Gulf nation's financial district.

On a wall along the street in the Bahraini town of Budaiya, a graffiti drawing depicts the King of Bahrain driving a racing car and the words: "Boycott Formula 1 in Bahrain."

This sentiment is shared by many Bahraini Shi'ites - the majority in the Sunni-ruled kingdom - who said the Formula One Grand Prix race Bahrain will host from April 19-21 should be cancelled, as it was in 2011 when authorities crushed pro-democracy protests inspired by the 'Arab Spring'.

The 2012 race went ahead with a heavy security presence around the circuit and frequent clashes between anti-government protesters and riot police during the nights.

Two years on daily clashes still erupt, largely unnoticed outside the region. But despite the mixed opinions, the race authorities indicated the race will go ahead as planned.

This year Formula 1 Boss, Bernie Ecclestone said the signs are that tensions in the kingdom have eased and the risk of protests has diminished -- a view opposition activists reject.

Watched by millions around the world, the Grand Prix is the biggest sporting event hosted by Bahrain and authorities are eager to showcase their country in its best light.

Presented by Adam Justice