Why Did Bobby Brown Leave Whitney Houston's Funeral Early?

Moments after Whitney Houston's funeral began, her ex-husband, Bobby Brown, was spotting abruptly leaving the service with his son Landon Brown.
So, why did the New Edition singer exit the church just 20 minutes after the funeral began?
MORE: Whitney Houston's Funeral: Moment by Moment
"My children and I were invited to the funeral of my ex-wife Whitney Houston," Brown said in a statement released to E! News.
"We were seated by security and then subsequently asked to move on three separate occasions. I fail to understand why security treated my family
this way and continue to ask us and no one else to move.
"Security then prevented me from attempting to see my daughter Bobbi-Kristina. In light of the events, I gave a kiss to the casket of my ex-wife and departed as I refused to create a scene. My children are completely distraught over the events. This was a day to honor Whitney. I doubt Whitney would have wanted this to occur. I will continue to pay my respects to my ex-wife the best way I know how."
Brown's agent, Jeff Allen, previously told E! News the singer left early to make it in time to his concert tonight (the New Edition show starts at 8 p.m. ET Saturday night in Connecticut). Twitter was abuzz with speculation of what might have gone down, due to tweets from the media and funeral-goers.
"I am at Whitney's funeral. I spoke with Bobby Brown trying to calm him down and not distract from the services. Today is about Whitney!," Al Sharpton tweeted. "I am going back in the services, I did my best out here. Can't tweet from inside the sanctuary, I hope the press will not distort the day."
MORE: Mariah Carey: Whitney Houston's Death "Was Tough," Says Hubby Nick Cannon
And there are also reports that Brown brought a "posse" that funeral organizers didn't want to accommodate.
A source told E! News that while they're not sure that was the reason Brown left, it was definitely an issue while he was in attendance.