A third person is being questioned by police on suspicion of murdering black teenager Anthony Walker.
Police say the attack on Anthony Walker was racially-motivated
Anthony, 18, was attacked with an axe by a gang of white men, in what Merseyside Police said was a racially-motivated attack.
A 23-year-old man from Huyton, Merseyside, was arrested on Thursday.
Michael Barton, 17, and Paul Taylor, 20, are still being held after they were arrested at Liverpool John Lennon Airport on Wednesday night.
The pair had gone to Holland but returned voluntarily, with a solicitor.
The men were taken into a police van after leaving the plane
Passengers on the 1820 BST easyJet flight from Amsterdam were allowed to get off the plane before police officers boarded to take the pair, who were also accompanied by relatives, away for questioning.
Mr Barton and Mr Taylor were arrested when they stepped on to the tarmac and got into a waiting police van.
On Tuesday, footballer Joey Barton, brother of Michael Barton, appealed for his brother to contact police.
He described the murder as "senseless and horrific".
Merseyside Police said Michael Barton and Paul Taylor were only two of a number of people they wanted to speak to about the attack in Huyton on Friday night.
Axe in skull
Anthony was killed after he was subjected to racial taunts while waiting for a bus with his 17-year-old girlfriend and a cousin, Marcus Binns, also 17.
The three walked away but were followed into a park where Anthony was attacked and an axe was left embedded in his skull.
He was taken to hospital but died later.
Police have already questioned four men who were subsequently released on bail.