The actor, writer and filmmaker died on Monday (24Feb14) from complications of a rare blood disease, and celebrities including Jon Favreau, Seth MACFarlane, Eli Roth and Stephen Fry were among the first to honour the late star via Twitter.com.
Now Aykroyd has added his tribute to his friend and collaborator.
A statement issued to The Hollywood Reporter reads: "(I am) deeply saddened to hear of the passing of my brilliant, gifted, funny friend, co-writer/performer and teacher Harold Ramis. May he now get the answers he was always seeking."
Aykroyd had been working with Ramis for some time to bring Ghostbusters 3 to the big screen, but it is not yet known how his death will affect the project.
Meanwhile, comedian Steve Martin has commented on Ramis' passing via Twitter.com, writing, "So sorry to hear about the death of Harold Ramis, a comedy master. Ghostbusters, Groundhog Day, and more", and actress Julianne Moore adds, "Very sad to hear that we lost Harold Ramis. Exceptionally talented, exceptionally kind."
And his Year One co-star Christopher Mintz-Plasse has also expressed his thoughts online, tweeting, "So lucky I got to work with Harold Ramis, even if just for a couple weeks. The nicest, most talented gentleman. God damnit. Rip."
Prehistoric comedy Year One, which was released in 2009, was Ramis' final movie as both an actor and director.