A Fremont man was sentenced to 70 years-to-life in prison Thursday following his first-degree murder conviction for the brutal stabbing death of a popular Newark high school football player nearly three years ago.

Daniel Howard, 31, of Fremont, was convicted of killing 17-year-old Justice Afoa in December 2010, a case compounded by new charges that he tried to hang his pregnant girlfriend from a tree in November 2012. He was convicted of attempted murder, premeditated attempted murder of a fetus, kidnapping and criminal terrorist threats in that case, said Eamon O'Connor, spokesman for the Alameda County District Attorney's office.

Prosecutors last December also charged Daniela Guzman, 19, and her stepbrother, Rafael Tovar, 32, both of Newark, with Afoa's murder, as well as conspiracy to commit murder and committing a crime to benefit a gang. A fourth person, Anthony Bernal, 23, was arrested in December on suspicion of assaulting Afoa and a friend at an October 2010 house party; prosecutors said Afoa's slaying was retaliation for that fight, which also involved Tovar. The three are awaiting trial.

Prosecutors said on Dec. 15, 2010, that Tovar and Howard hid behind a wall on Cedar Boulevard at Birch Street, about a quarter-mile from Newark Memorial High School, waited for Afoa to walk by, then jumped out and confronted him. Afoa ran, but Tovar caught up and stabbed him five times with a kitchen knife, prosecutors said. Howard also reportedly stabbed Afoa at least five times with an unidentified weapon. He died at the scene.

Afoa's best friend and Newark football teammate, Osana Futi, was himself stabbed to death in April 2012. A judge in May sentenced a 19-year-old alleged Fremont gang member, Abraham Hade, to 16 years to life in prison for that crime, three months after Hade was convicted of second-degree murder.

"This was such a sad case," O'Connor said of the stabbing deaths of Afoa and Futi just 16 months apart. "It was almost like a Romeo and Juliet story."

Howard was already in custody on charges he tried to hang his pregnant girlfriend, Alma Rosalez, from a tree at a Fremont home in the 41500 block of Beatrice Street on Nov. 25, 2012. The murder of Afoa and the attempted murder of Rosalez were combined into one case, and further complicated by prior convictions in 2001 and 2003 for assault with a firearm and false imprisonment.

Contact Erin Ivie at eivie@bayareanewsgroup.com. Follow her at Twitter.com/erin_ivie.