What does "there's only so much I can tell you" (3rd paragraph) mean?
"only so much" sounds confusing to me.

Context>>>>>>>
"We are trying to talk to this male, trying to let him know that he can end this peacefully now," Ross said. "We have called him multiple times. He's picked up the phone a couple times, but he has not answered.

He said officers have been working with a family member of the suspect in an effort to reason with the shooter.

"Despite several attempts to talk to him -- both on the loudspeaker and on telephone -- we have been not been able to make contact with them thus far," Ross said. "This is a very volatile situation that is still unfolding, so as a result there's only so much I can tell you about what's going on inside of that property."

One woman said she heard over 100 gunshots and saw people running for their lives.

"I heard so many gunshots ... I'm scared," she told WPVI.