They were also charged with criminal conspiracy, police said, adding that three people had been arrested so far.
The government has pledged to set up a fast-track court to prosecute the crime, which took place earlier this week in the state of Uttar Pradesh.
Alleged police inaction sparked outrage in the teenagers’ village.
The father of one victim said he was ridiculed by police when he sought help in finding his missing daughter.
He said that when policemen found out he was from a lower caste, they “refused to look for my girl”.
Authorities said on Friday that they were still looking for two other suspects.
Senior police official Atul Saxena earlier announced there would be a “thorough investigation” into the allegations of caste discrimination by police.
Divisions between India’s castes run deep, and violence is often used by upper castes to instill fear in lower castes, correspondents say.
Although both the victim and the accused belonged to a caste grouping known as “Other Backward Classes”, the victims were lower in that hierarchy.
The girls, two cousins aged 14 and 16, went missing in Badaun district on Tuesday night. They had apparently gone out to relieve themselves as they had no toilet at home.
Their bodies were discovered the following day. A post-mortem examination confirmed multiple assaults and death due to hanging.
Campaigners have highlighted the lack of sanitation in rural areas as being a risk to women’s security as well as their health, as they are often attacked when having to go out to use the toilet, particularly at night.
Some women’s groups argue that the low conviction rate for rape should be challenged with more effective policing rather than stiffer sentences.
HWrpgCD72wEImage source: Wikimedia Commons President-elect Donald Trump celebrated his election victory at the Ultimate Fighting…
Millions of voters across the US chose to return Donald Trump to the White House…
Donald Trump declares victory in the US election as he addresses jubilant supporters in Florida.…
Stocks around the world are rising as Donald Trump appears to be on the cusp…
Donald Trump has won Pennsylvania, North Carolina and Georgia and taken a lead over Kamala…
Quincy Jones, the celebrated musician and producer who worked with Michael Jackson, Frank Sinatra, Ray…