On 27 September 2008, at approximately 14:15, a bomb exploded in the Sarai electronics market area of Mehrauli, a locality in Delhi, India. According to eyewitness accounts reported by Wikipedia, two men dressed in black and wearing helmets rode up on a motorcycle and dropped a tiffin box containing the device. A thirteen-year-old boy named Santosh, who was running an errand to fetch a crate of eggs for his uncle, picked up the box intending to return it to the men, who refused it and fled. Bystanders noticed smoke coming from the box and warned the boy to move away, but the device exploded before he could escape. Santosh was killed in the blast, and 18 others were injured in the initial reporting; the death toll rose to three the following day, with about 23 people injured in total. The injured were treated at AIIMS and Fortis Hospital. The Washington Post reported that seven of the injured were in critical condition. The attack occurred exactly two weeks after a series of five coordinated bombings struck four locations in Delhi on 13 September 2008.
In the aftermath, the Chief Minister of Delhi announced compensation of Rs. 500,000 for the families of the dead and Rs. 50,000 plus treatment costs for the injured. Indian political leaders, including Pranab Mukherjee and Lal Krishna Advani, condemned the bombing, while the opposition Bharatiya Janata Party criticized the government's counterterrorism approach. A survey by CNN-IBN and Hindustan Times found that a large majority of urban Indians reported feeling scared following the wave of attacks and favored stronger anti-terrorism laws. Local reporting noted that Delhi's usually busy shopping areas appeared deserted in the days following the blast, and shopkeepers avoided the Mehrauli flower market near the blast site. Security for the touring Australian cricket team was also tightened, though Cricket Australia confirmed its scheduled test match in Delhi would proceed.
The investigation, assisted by the National Security Guards, found that the device used ammonium nitrate, sulphur and potassium and was a low-intensity bomb without a timer or detonator, according to Deputy Commissioner of Police Alok Kumar. Investigators noted similarities to earlier bike-borne bombings near IIT Delhi and Lado Sarai earlier in 2008. Police detained several individuals for questioning, including five people at Indira Gandhi International Airport and a man in Faridabad accused of selling the SIM card used to make a warning call to media before the blast. Police stated that a caller had warned, "Save Delhi, there will be blast!" prior to the explosion. Investigators said they did not believe the Indian Mujahideen, which had claimed responsibility for the 13 September attacks, was responsible for this bombing, citing differences in the bomb's construction. Police also stated that the explosive's design differed from bombs used in the Malegaon and Modasa blasts, and Hindu groups under scrutiny in those cases were ruled out as suspects in the Mehrauli bombing. No individuals were reported as charged or convicted in connection with this attack based on available reporting.