Update at 19:45, Friday 19th May
Statement by the Maurizio Bufalini Hospital in Cesena (Italy):

"The clinical picture of Nicky Hayden remains unchanged. His condition is still extremely critical.

"He is still in the intensive care unit of Cesena's Maurizio Bufalini Hospital and the prognosis stays reserved."

Update at 10:00, Friday 19th May

MotoGP's official twitter account has given a brief update:

"Hayden remains in an extremely serious condition in the Intensive Care unit in hospital.

"The prognosis remains guarded."

The Red Bull Honda World Superbike Team has given a new update on Nicky Hayden, describing his condition as 'extremely critical'.

The former MotoGP World Champion was seriously injured in an accidet whilst cycling near Misano in Italy.

Honda's latest update, at 16.00GMT, says Hayden has suffered a 'serious polytrauma with subsequent serious cerebral damage'. His condition remains 'extremely critical'.

He has now been joined by his family.

Full statement below

'The Red Bull Honda World Superbike Team would like to share the latest news on Nicky Hayden.

'As well as having his fianc? Jackie by his side, Nicky has now been joined by his brother Tommy and mother Rose who arrived in Italy from the United States earlier today.

'Below is a statement on Nicky's condition from the Maurizio Bufalini Hospital in Cesena, Italy.

"Nicky Hayden's clinical condition remains extremely critical.

"The young man, who is still in the intensive care unit of Cesena's Bufalini hospital, has suffered a serious polytrauma with subsequent serious cerebral damage.

"The prognosis remains reserved."'