According to the law, homosexuality is an offence punishable by death and someone suspected of "aggravated homosexuality" can be sentenced to lifetime imprisonment.
The anti-gay legislation, which prescribes the death penalty for some homosexual acts, was signed into law in May.
"So far 20 people have been confirmed dead, and nine (9) rescued," the Uganda police force said on Twitter, which is being rebranded as X.
The accused were Lydia Willibad Ulotu, a Tanzanian national and Osama Rayner alias Ray, a Nigerian citizen.
Following persistent efforts of a deceased 47-year-old man's family, his body was brought back from Uganda to his native Madurai on Sunday.
In a report due to be published this week, UN experts on the DRC shed light on the hazy financial connections between the two groups.
The Allied Democratic Forces, which has links to the Islamic State, shot, burned and hacked the children to death, authorities said.
Police and army officials blamed the ADF, one of the deadliest militias over the border in DR Congo's strife-torn east, which the Islamic State group has called its local offshoot.