"The two criminals who shot him did not steal the car or anything else."
Tony Gachoka, an ODM spokesman, said: "He was shot at his house. The current situation makes one suspicious. All fingers will point at the government, and the government will have to show it is not involved."
Police fired tear gas at mourners who gathered at Were's home and allegedly taunted officers.
'Not a political murder'
Al Jazeera's Yvonne Ndege, in Nairobi, said that the police had told her that they are not treating this as a political murder. Instead they say one of the city's frequent violent crimes, such as a car jacking, may have led to the death.
Yet Ndege said there's "every possibility" that Were was killed by a rival candidate for the seat in the December 27 legislative vote, held at the same time as presidential elections. The seat is now vacant after Were's death.
She added: "As a consequence of this there has been some fighting taking place in Kibera - one of the biggest slums in Africa and an opposition stronghold - where people on the ground have reported seeing at least two bodies.
"In Mr Were's constituency, called Embakasi, there is a lot of tension. Apparently rowdy youths have been gathering in the market and several kiosks have been burned."
Salim Lone, another ODM spokesman, had appealed for calm: "Let's call again on people to be peaceful and to only respond to this kind of violence by shunning violence."
President Mwai Kibaki was declared victorious in the presidential elections, a disputed result which has led to upsurges of violence around the country, particularly in the Rift Valley province.
Soldiers moved into the town of Naivasha in the province in western Kenya the day before in an attempt to quell tribal fighting that has cost dozens of lives.
Katee Mwanza, the district commissioner, said at least 22 people had been killed in the Naivasha area in ethnic clashes over the past two days, with police saying at least five were burned to death.
Reports said that people's homes were ransacked and burned in Naivasha on Tuesday.
Ndege said that there had been very little progress on negotiations between the government and opposition. She added that Kofi Annan, the former UN secretary general who is mediating talks, is waiting to see if the three negotiators from each side he has requested will be put forward.