West Yorkshire police are investigating after reports of the boy being attacked with a weapon from Ovington Drive, Homewood.
The officer was called to the area just after 7pm on Sunday, and last night there was a social media report about the presence of large-scale emergency services on the property.
One said he found at least 20 officers and a police dog unit in the area.
The 15-year-old boy was injured.
According to a West Yorkshire Police spokesman, he was taken to hospital with life-threatening injuries.
They added: “Inquiries are underway by Bradford CID.”
Members of the public reported last night that they saw a police helicopter hovering over Homewood.
Telegraph & Argus contacted the National Police Air Service (NPAS) for confirmation.
An NPAS spokesperson said he was called to another incident in the area at 8:488 p.m.
The team was asked by West Yorkshire Police to assist in a vehicle search in the Ton area of Bradford, leaving for a total of 25 minutes.
Police would like to talk to anyone who witnessed the attack in Homewood or has information to help investigate.
If you can help, you will need to contact 101 units or use the contact options on the West Yorkshire Police website.
The crime reference number must be quoted: 13250193566.
Alternatively, you can provide details anonymously to independent Charity Crimestoppers online or on 0800 555 111.