WASHINGTON (Reuters) - Six people were killed and more than 20 wounded in indiscriminate gunfire in the western Texas cities of Odessa and Midland, police said on Friday.

The same source said that among the dead was the bomber, a "white man" as reported, and said that there is no gunman at large at the moment.

A gunman hijacked a postal car and shot people randomly, state media quoted state police as saying.

"One (maybe two) drive around Odessa and shoot randomly at people," Odessa police said on Facebook.

"There are several shooting victims at the moment. The suspect has just hijacked a US mail truck," she said.

US police said on Saturday that 10 people were injured by gunfire inside a soccer field in Mobile, Alabama, and that five of the wounded were in serious condition.

The CNN quoted police as saying that the wounded were between 15 and 18 years old.

The United States has witnessed frequent shootings, resulting in deaths and injuries.