Be careful with that choice of words, some idiot has apparently fired a couple of "model" rockets at CO Express aircraft in the Houston area!
Hunt for rocket that nearly hit jet in Texas
I think it unlikely they were fired at the aircraft if it was at 13,000 feet. Amateur rockets can be impressive but generally aren't fast enough to be launched as the aircraft goes overhead. They would need to be launched when the aircraft is still several miles away. Much more likely the rocketeers just weren't keeping a good look out. No excuse mind.