Robert Fisher, added in June 2002, $100,000 reward
In 2001, Fisher allegedly killed his wife and two children, then blew up their house in Scottsdale, Arizona, according to the FBI.
The Bureau says Fisher is physically fit, and has a noticeable gold crown on his upper left first bicuspid tooth.
"He may walk with an exaggerated erect posture and his chest pushed out due to a lower back injury."
Fisher can be seen walking and carrying one of his children before committing the alleged massacre in this very grainy video from 2001.
Alexis Flores, added in June 2007, $100,000 reward
Flores is wanted for his alleged involvement in the kidnapping and murder of a 5-year-old girl in Philadelphia.
She was reported missing in July of 2000, and later found strangled to death in a nearby apartment that August.
He has scars on his right cheek and forehead, according to the FBI.
Jason Derek Brown, added in December 2007, $200,000 reward
Brown is wanted on charges of murder and armed robbery in Phoenix, Arizona. In 2004, he allegedly shot and killed an armored-car guard outside a movie theater and then fled with the money.
Brown, a Mormon, speaks fluent French and has a masters degree in international business.
He "enjoys being the center of attention and has been known to frequent nightclubs where he enjoys showing off his high-priced vehicles, boats, and other toys," according to the FBI.
Eduardo Ravelo, added in October 2009, $100,000 reward
Ravelo, also known as 'Tablas," is part of the Barrio Azteca criminal enterprise. Members of this group act as hit men for the Vicente Carrillo Fuentes Drug Trafficking Organization and are responsible for numerous murders, according to the FBI.
Ravelo is wanted for alleged money-laundering, racketeering, and drug-related activities in Texas. He also is accused of committing several murders in Mexico.
Like many of the FBI's most wanted criminals, it is believed that Ravelo had plastic surgery and altered his fingerprints to further evade authorities.
William Bradford Bishop, Jr., added in April 2014, $100,000 reward
Bishop is wanted for allegedly beating his wife, mother, and three sons (aged 5, 10, and 13) to death in 1976 in Maryland. The FBI says he then brought their bodies to North Carolina, where he buried them in a shallow grave and lit them on fire.
Bishop graduated from Yale University and has his master's degree in Italian from Middlebury College in Vermont. He also had extensive camping experience in Africa, and enjoyed canoeing, fishing, swimming, jogging, tennis, skiing, and riding motorcycles. He even learned to fly as an amateur pilot in Botswana.
Before the killings, Bishop was reportedly under psychiatric care and was using medication for depression.
The FBI notes that Bishop was "described as intense and self-absorbed, prone to violent outbursts, and preferred a neat and orderly environment."
Yaser Abdel Said, added in December 2014, $100,000 reward
Said is accused of murdering his two teenage daughters in 2008 in Texas.
He is originally from Egypt, but has ties to New York, Texas, Virginia, and parts of Canada.
The FBI notes some oddly specific details about Said.
"He always wears dark sunglasses, both indoors and outside. He frequents Denny's and IHOP restaurants and smokes Marlboro Lights 100 cigarettes," the FBI says.
Said also "loves dogs, especially tan and black colored German Shepherds."
Bhadreshkumar Chetanbhai Patel, added in April 2017, $100,000 reward
Patel, who is from India, allegedly killed his wife by hitting her repeatedly with an object while they were both working at a donut shop in Maryland in 2015.
He was charged with first and second degree murder, first and second degree assault, and carrying a dangerous weapon with intent to injure.
Patel fled in an effort to evade authorities. He is last known to have been in the Newark, New Jersey, area.
Santiago Villalba Mederos, added in September 2017, $100,000 reward
Mederos is a member of the Eastside Lokotes Sureno gang, which is located in parts of Washington State, according to the FBI.
He is accused of killing a random 20-year-old girl and wounding her brother after shooting at them in their car in 2010.
A month later, Mederos allegedly fired again at random bystanders, killing a 21-year-old man.
Alejandro Castillo, added in October 2017, $100,000 reward
Castillo fled the US after allegedly killing his ex-girlfriend and former co-worker in North Carolina.
US Customs and Border Protection surveillance video shows him crossing the border into Mexico from Nogales, Arizona, in August 2016.
The female victim's body was found in a wooded area in North Carolina with a gunshot wound to the head, according to the FBI.
Castillo previously lived in Charlotte, North Carolina, but has connections to Arizona.
Jesus Roberto Munguia, added in November 2017, $100,000 reward
Munguia, a convicted felon, is an alleged member of the TEPA 13 gang, which is based in the Los Angeles and Bakersfield areas of California.
In July 2008, Munguia reportedly kidnapped and murdered his wife in Las Vegas, according to the FBI.
A local court charged him with first degree kidnap and murder with a deadly weapon.