One of Hip Hop's most influential emcees is presently in critical condition, several sources say. Guru, one half of pioneering '80s, '90s and '00s Brooklyn-based Hip Hop group Gang Starr suffered a heart attack this weekend, according to the emcee and producer's sister Tricia.

HipHopWired.com says that the emcee, born Keith Elam is presently in a coma from complications of going into cardiac arrest. Guru is best known for penning hits such as "Words I Manifest," "Discipline" and "Just To Get A Rep." Between 1986 and 2004, Guru (an acronym Gifted Unlimited Rhymes Universal) founded Gang Starr, a duo with DJ Premier that also includes Gang Starr Foundation affiliates Big Shug, Group Home, Jeru Da Damaja and Smiley Da Ghetto Child.

Born and raised in the Boston area, Guru relocated to Brooklyn in the late '80s, where Gang Starr released its first singles with 45 King as producer. By 1988, the group evolved as a duo with Premier, and released their 1989 full-length debut No More Mr. Nice Guy on Wild Pitch Records. The duo would go on to release classic albums on Chrysalis/Virgin/EMI, such as 1994's Hard To Earn and 1998's Moment Of Truth. Gang Starr's last album, 2003's The Ownerz featured Jadakiss, Fat Joe and longtime affiliate Freddie Foxxx. The platinum group toured the world and released several greatest hits collections, most notably Full Clip: A Decade Of Gang Starr in 1999. The duo announced their split in 2004, reportedly due to creative and personal differences.

As a solo artist, Guru released four volumes of Jazzmatazz, Jazz-inspired recordings with legendary genre artists such as Donald Byrd and Roy Ayers. Guru has launched two labels in his career, Ill Kid Records and 7Grand, where he and production partner Solar worked alongside artists such as Talib Kweli, Damian Marley and Jean Grae.

HipHopDX extends prayerful thoughts to one of our staff's most-respected emcees, the Elam family, Solar, DJ Premier and fans. We will keep you updated.

UPDATE: Miss Info confirms these reports with sources close to Guru. The emcee is presently in a New York hospital, awaiting surgery. DJ Eclipse spoke with DJ Premier, who also confirmed this. Premier was going to address the matter on Eclipse's Sirius Hip Hop Nation show, but later changed his decision.

NahRight.com has compiled Twitter reactions from notable artists including Jean Grae, ?uestlove, Royce Da 5'9" and Jay Electronica.

UPDATE: Solar, Guru's production partner and co-founder of 7 Grand Records released a statement to HipHopDX through his spokespeople at Yo! Public Relations. The statement is as follows, "Guru is struggling with a serious health issue. We, the whole 7 Grand Records family, appreciate all your love and well wishes. We continue to hold out hope that Guru will make a full recovery from this. We ask that his privacy on this matter will be respected. Again, thank you for all your support through this trying time."