Manu Tuilagi and Denny Solomona have been sent home early from the England pre-season training camp in Teddington.
The RFU say the pair have been disciplined because of "team culture issues", which are understood to be alcohol-related.
The players are believed to have gone out drinking on Sunday evening and contravened the team's standards of behaviour.
The three-day camp in Middlesex was due to finish on Monday.
It is understood the England players all went out as a squad to dinner locally, and returned to their hotel as a group.
England head coach Eddie Jones rarely enforces alcohol bans or curfews on his players, but Tuilagi and Solomona then left the hotel for a second time, returning in the early hours of Monday morning, thought to be as late as 04:00 BST.
It is the first time since taking the job almost two years ago that Jones has disciplined individuals for off-the-field behaviour.
Jones said last week he would be prepared to pick Tuilagi, 26, as early as the autumn internationals in November.
The Samoa-born Leicester centre has not played for England since March 2016, and has been out of action since January because of a knee injury.
He has a history of disciplinary issues, and was left out of England's 2015 World Cup squad after being fined for assaulting two female police officers.
Leicester head coach Matt O'Connor said the club would speak to Tuilagi on his return, adding the news was "particularly disappointing because Manu has worked so hard to get back to fitness after long-term injury and to get back into the England squad".
Sale Sharks winger Solomona controversially switched from rugby league to union last year.
The 23-year-old, who was born in New Zealand, scored the winning try on his England debut against Argentina in June.
Sale director of rugby Steve Diamond said: "This is disappointing news because Denny has worked so hard since joining the club last December. He hasn't had much time off and his performances earned him a place on the recent England tour to Argentina.
"This matter has been dealt with by the RFU and I will speak to Denny on his return."
England face Argentina, Australia and Samoa in November.
"If he's fit and ready to go, we'll play him," said Jones before the training camp of Tuilagi, who has been capped 26 times.
"He demolished New Zealand before, and if he's fit and he's got the right desire, then he's always got a chance to get selected for us."
Tuilagi's previous problems
- 2010 - Avoided deportation after it was found he had remained in England for six years on an expired visa
- 2011 - Banned for five weeks for punching Northampton's Chris Ashton; misses Premiership final against Saracens
- 2011 - Warned by police and fined £3,000 by England rugby officials after jumping from a ferry in Auckland a day after England's quarter-final World Cup exit
- 2013 - Makes 'bunny ears' gesture with two fingers behind then Prime Minister David Cameron's head while posing for a photo with British and Irish Lions players
- 2015 - Fined £6,205 by magistrates after admitting assaulting two police officers
As recently as Friday, England head coach Eddie Jones was eulogising about what a fit and firing Tuilagi could bring to the fold, but the Australian is likely to take a dim view of this latest disciplinary lapse.
Both players have shown a lack of judgment; Tuilagi needs to let his rugby finally do the talking after a couple of injury-plagued years, while Solomona has only just broken into the set-up after controversially moving from rugby league and then qualifying on residency.
I understand Jones has yet to decide how this incident will affect the pair's prospects going forward, but it will surely do their chances no good whatsoever.