Some Kenyan commuters walked for several miles
Tens of thousands of Kenyan commuters have been left stranded or forced to walk long distances because of a strike by minibus-taxis known as matatus.
The matatu operators say they are protesting against harassment and extortion by police.
But the police have accused the operators of refusing to comply with traffic laws.
Matatus are the main mode of transport in towns across the country. The strike is planned to last until Wednesday.
The matatus last went on strike in 2003 over new safety rules, but their protest fizzled out as the measures had strong public backing.
The BBC's Josphat Makori in Nairobi says implementation of the measures lapsed until a new police boss took over, sparking the latest protest.
Strikers 'are blackmailers'
Dickson Mbugua, spokesman for the matatu workers, said they would move to "option B" if nothing was done by Wednesday - though he refused to say what that would be.
He told the BBC's Focus on Africa programme the police board the minibuses and demand bribes from the drivers.
"They don't tell the driver why they want to impound it," he said.
"They just say: 'This vehicle is unroadworthy, either it goes for inspection or you give me 2,000 or 3,000 (shillings)."
But Nairobi police chief Eric Kiraithe dismissed the allegations as untrue and claimed the police had acted to combat corruption.
"Last year alone 26 police officers were prosecuted for various offences related to traffic - bribery and all that," he said.
He accused the strikers of "blackmail", adding: "The people calling for a strike aren't interested in the welfare of the people."
Several commuters making their way through the Nairobi rain told the BBC they were angry over the strike and would not be supporting the matatu workers.
Thanks for your comments. You can read a selection below:
After all has been said and done, the strike is finally over. As a journalist, and having to cover the strike, I was able to take in the full brunt of it all. Business outlets: restaurants, shops, supermarkets, basically all business outlets, have not conducted business in these two days of the strike and in the process lost lots of money running into hundreds of millions of shillings. The government has not been left out too. Apart from losing millions of shillings in uncollected revenue, in the two days, it lost more millions in wasted manpower as numerous civil servants were unable to report to work. The strike has exposed the country's underdevelopment in the transport sector. That private owners of buses could paralyse business activities as well as any other activity at will is a wake up call to government. I hope from now the newly created Nairobi metropolitan ministry will think in terms creating a reliable cheap, and efficient transport system to come in handy whenever matatu owners think of blackmailing the nation. It wasn't a pretty sight seeing a nation that loves to work, being turned into a nation that 'loves' to walk. Am glad it's all over. On a lighter note, Can my fellow Kenyans think of the positive impact we have had on our health and on mother earth by having not to use those filthy, smoke bellowing, and environment polluting matatus for a refreshing, fat burning, sight seeing, walks to work.
Brian Ngugi Njoroge, Nairobi, Kenya
The strike is affecting even schools and colleges as opening day was yesterday. Common citizens are really suffering.
The matatu strike is on its 2nd day and it has caused heavy losses to business. My employees are even two hours late and this has caused my customers to be unhappy. I would like the matatu operators and the police to have some sort of understanding to end this crisis before tomorrow.
Pauline swagi, Nairobi, Kenya
Yes today I woke up very early at 0500hrs and set out to work on foot, but still I arrived late and am tired at work. Again I intend to close early and start the trek back home though my boss may not smile about it. It is true some Matatu (psv Vehicles) are not compliant with road safety rules but again the Traffic police are also very very corrupt here in Kenya. Whether your psv vehicle is good or bad, just bribe them - you'll get away with it and if not; get arrested, your vehicle impounded and towed away at your cost, then be taken to court where almost all presiding Judges perfunctorily impose prohibitive fines on the Matatu never bothering to check if the police allegations are true or false. One suggestion is to have a team of both matatu and traffic police representatives sitting at traffic headquarters to independently verify the allegations against each impounded vehicle. I wish all Kenyans a happy bribe free 2010!!!
Thomas Ndemo, Nairobi, Kenya
I am in Eldoret, most passengers were stranded in the morning coursing people to wait for the few matatus which were operating in town, students were the most affected because most of them were to report to their various schools.
alex kiptoo kipyegomen, kenya
We will just have to bear and grin - but I totally support the police crackdown - it is about time the crazy matatu operators respected the law. The can't be a law unto themselves. Let us see who will outlast who?
Jerry, Nairobi, Kenya
Here in Kisii, operations are normal. Its only long distance travellers who have been affected. Police should stop soliciting for bribes
Angwenyi Wisdom, Kisii,Kenya
I was in town this morning having travelled by night bus from upcountry. I waited at the stage for almost an hour in the pouring rain. In the end I had to call a taxi which cost me ten times the normal fare. The taxi man is a friend from the University of Nairobi. On the way I saw men women and children coming back from the holidays walking with heavy luggage.
Ochiel J Dudley, Nairobi