George Zimmerman, the 28-year-old Florida man who shot and killed a 17-year-old in his Sanford gated community, repeatedly called 911 over the past 14 months, and in several instances warned of “suspicious persons” who, like Trayvon Martin, happened to be black.

The Seminole County Sherrif’s Department released several such calls Monday, amid intensifying calls for Zimmerman’s arrest for the killing of Martin, who was walking to his father’s house from a local store February 26th when he was followed, and then fatally shot by, Zimmerman.

The six newly released 911 calls, none of which relate to the Martin shooting, show Zimmerman worried more than once about unknown persons walking through the neighborhood.

From the Orlando Sentinel:

In four of the recordings Zimmerman called police to report “suspicious” persons — all of whom were black — in or near the Retreat at Twin Lakes neighborhood.

He called once to report his neighbor’s open garage door. And in the sixth call, Zimmerman reports children are “habitually” playing in the street at dusk and running in front of cars. He asked dispatchers to take his complaint anonymously, but provided his name and phone number.

Sanford police have declined to arrest Zimmerman, saying witness accounts support his claim of self defense. But that claim is disputed by at least three witnesses, and by Martin’s family.

Protests are planned for Thursday, continuing the calls for Zimmerman’s arrest.