A crack in the floor which forms Tate Modern's latest installation has claimed its first casualties.

Three visitors lost their footing and fell into the gap made by Doris Salcedo's art work.

They were among more than 12,000 people who viewed the installation, which runs the full 167 metres (548 feet) of the Turbine Hall.

The Tate said the trio did not sustain serious injuries.

"We can confirm that three visitors missed their footing and tripped in the Turbine Hall at the opening event.

"They were attended to immediately by Tate security staff trained in first aid but there have been no serious injuries. Twelve thousand people visited the installation on the first day and there have been no further incidents," a spokeswoman said.

"Tate staff are monitoring the space carefully to ensure the safety of our visitors.

"Tate has a lot of experience handling complex installations and visitor safety. We have thought carefully about visitor safety, working closely with Southwark Council and there are measures in place. There are no plans to barrier off the work at this stage."

Tate staff are on hand with leaflets warning about the dangers of getting too close to the piece.

Gallery attendants have also been instructed to give verbal advice to visitors.

Brazilian sculptor Salcedo says the work, entitled Shibboleth, symbolises racial division.

The crack represents the gap between white Europeans and the rest of the world's population.

According to Salcedo, the fissure is "bottomless... as deep as humanity".

However, it appears to be around three feet at its deepest point.

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