Police officials said the explosion occurred in the middle-class
residential district of Nand Nagri just before 6am local time.
"The explosion occurred near a railway crossing and one person was injured," police sub-inspector Subodh Singh said.
No further details of the explosion were immediately available.
Earlier, two bombs exploded inside two cinemas showing a controversial Hindi-language film in the Indian capital, killing one person and injuring at least 49 others.
Both theatres are in the Karol Bagh neighbourhood of west Delhi and the explosions occurred 15 minutes apart on Sunday, Junior Home Minister Sriprakash Jaiswal said.
"The explosion occurred near a railway crossing and one person is injured"
Delhi police sub-inspector
At least 43 people were injured in the first blast at the Liberty Cinema at about 1500 GMT, according to a list of injured pasted by police outside the theater.
One of the injured died later at a hospital, the Press Trust of India news agency reported.
The explosive was planted under a seat in the front rows, Chief Fire Officer R C Sharma said. Sikhs offended
About 15 minutes later, another explosion rocked the nearby Satyam Cinema, wounding at least seven people, he said. At Satyam, the bomb went off inside the washroom.
Authorities evacuated cinema halls in other parts of the city after the blasts, and security forces in the capital were put on high alert.
The two theatres were cordoned off by police and fire fighters.
The two theatres were showing a film called Jo Bole So Nihal.
Some Sikhs say the title, in the Punjabi language, offends their religion.