After an alleged gang member is shot in the back and killed by police now comes word that there have been threats of retaliation against the Houston Police Department. Threats from a gang that has been terrorizing neighbors is now promising to do the same to police.

If there has ever been a doubt over who claims turf in the 6200 block of West Bellfort, then take a walk with reformed gang-member Sammy Rodriguez.

“That turf or area belongs to them, they've claimed that,” said Rodriguez pointing to symbols that a gang claims the area as its turf.

The initials LTC, which stand for La Tercera Crips, Houston's oldest Latino gang, are, scrawled almost everywhere.

So are R.I.P and the letter "H" referring to Alex Rivera, the robbery suspect police fatally shot in the back two Saturdays ago.

“Someone has done this in remembrance of someone. Someone got shot or killed in the area,” Rodriguez said as he explained what the markings mean.

But the taggings also convey ominous warnings. 11 News found one aimed at police Monday.

City workers covered it up over night.

“The quick action is indicative of the concerns surrounding LTC. In fact, 11 News learned the FBI is working closely with police to monitor the gang's recent activities and sharp rhetoric.

Our cameras captured the billowing anger just after the shooting. Days later police confirmed Rivera was a documented member of LTC, and told us fellow gang members wanted revenge against those he allegedly robbed.

“The gang members in the area are blaming them. If they hadn't called the police, none of this would have happened,” said Rodriguez.

A common mode of intimidation, making a businessman hide from our cameras.

"It's scary,” he said, avoiding the camera lens.

And the tactics forced a mother to hide her children indoors.

“Because you don't know what's going to go around the corner,” the unidentified woman said. “Somebody could be shooting and my child is in the crossfire.”