The protest leader wants to launch rallies in over 80 cities to give Putin a wake-up call.
"RIP cousin... can't believe it was just last night that I held you in my arms!" Rihanna posted on Instagram
The 29-year-old was a regular presence during protests.
The president spoke at the FBI Academy in Quantico.
The former interim chairwoman of the Democratic National Committee wrote about the unsolved murder of Seth Rich in her new book.
Rich's mysterious death was the subject of conspiracy theories.
The president used similar language after the Manchester attack in September.
Eight people had been killed and others injured after a truck ran into pedestrians in New York.
Sheryl Stiles's family thinks she may have died of a broken heart.
Chechen authorities deny all reports that they jail and torture gay men, but friends of a Russian singer fear for his life after he disappeared on a visit to the region.
Vitaliy Milonov also wants to ban Russians from transitioning from one gender to another.
The president suggested his predecessor did not call the families of fallen soldiers.
The head of the Philippine military said only about 30 militants remained in the formerly ISIS-held city and that victory would come "in a matter of days."
Jones, who was married to British Jihadi Junaid Hussain, was said to have been killed near the Syria-Iraq border.
"Scariest moment of my life," one Instagram user wrote, posting video of the terrified crowd. "They just kept firing and firing."
The deadly stabbing attack in Dagestan follows a similar incident in Siberia that left eight people injured, according to reports.
In a series of tweets, Clinton condemned white supremacists for inciting violence in Charlottesville that led to the death of one person and injuries of several others.
The trend is a significant spike as the death toll exceeds the 36 estimated by Reuters to have been killed in Syria over the previous 15 months.
The children's father was killed three days before they were born.