Crystal Palace's Carling Cup game against Crawley Town on Tuesday night and Bristol City's match with Swindon have both been called off.
The police contacted Palace and Crawley due to concerns over the ongoing riots in London and the cup tie at Selhurst Park will now have to be rearranged for a later date.
Bristol City's game against Swindon has also been postponed due to safety reasons following police advice.
West Ham and Charlton's fixtures, at home to Aldershot and Reading respectively, had already been postponed due to the disturbances in the capital.
Crawley had been preparing for their debut in the competition after beating fellow promoted side AFC Wimbledon in a qualifier on 29th July.
"I think we've all seen the news on Sky and we've all followed it," said Crawley boss Steve Evans.
"Late last night I got the call from the chief executive to say the police had been in touch with Palace and ourselves, so I think it was inevitable when you hear what is happening in West Ham and Charlton."
Following the violence in London, trouble spread to other cities including Birmingham, Liverpool and Bristol.
Speaking about his side's postponement, Bristol City chairman Colin Sexstone told the club's official website: "It's disappointing but we totally understand the reasons given by the police.
"Clearly the most important factor is people's safety and these are exceptional circumstances the police are dealing with."