Police said anyone breaking the law or displaying antisocial behaviour at this year's Grand National race festival will be dealt with firmly - as a range of extra security was announced.


Some 150,000 people are expected to attend Aintree Racecourse for the three-day event.


Last year's Grand National race was delayed by animal rights protestors.


Sup Int Matthew Moscrop, of Merseyside Police, said criminal activity "will not be tolerated".


The Randox Grand National is one of the biggest events in the sporting calendar and is watched by an international television audience of around 800 million people.


The Animal Rising group, whose protest caused a the delay to the race in 2023, said it does not intend to disrupt this year's race.


Sup Int Moscrop said the force was working with the Jockey Club and British Transport Police to ensure any incidents during the event are dealt with "effectively and efficiently".


Security checks include bag searches and badge checks will be under way, and only pre-booked vehicles will be allowed into Aintree.


Racegoers are also encouraged to report anything suspicious to police.


"As ever, we are expecting a large number of visitors to Aintree, and it is another prime opportunity to showcase what Merseyside has to offer," Sup Int Moscrop said.


"Anti-social behaviour, hate crime, disorder and other criminal activity will not be tolerated and will be dealt with robustly."


Plain clothes police officers will also be deployed at the event to monitor crowds.


"These officers are specially trained to spot the tell-tale signs that someone may have criminal intent, such as gathering information that may help them plan or prepare to commit a crime," Sup Int Moscrop said.


"As with all big events, a considerable amount of planning from all partner organisations has been done in the run up to the three-day festival to ensure everyone who attends has a great time, and that it is memorable for all the right reasons."


The festival begins on Thursday, with the flagship Grand National race taking place on Saturday at 16:00 BST.