Clue: Way to clamp down on breaking news (4,5)
Answer: STOP PRESS
Explanation: Definition: breaking news
 ST(abbrev. for "street"/a thoroughfare/a way) + OPPRESS(to clamp down/to subject to hardship).
Defn: News in a newspaper entered at the last moment just before printing began, or after printing has begun.
The clue could also be read literally since stopping the printing press(es) could be a method of stopping news from breaking/being sent out.