Saturday: a shoot-out between rival cartels in the north-western state of Sinaloa leaves nine dead, including six peasant farmers caught in the crossfire.
Sunday: gunmen burst into a wedding in a small rural town in the southern state of Guerrero, killing five.
Monday: hitmen target two people driving in Ciudad Juárez. The scene recalls the murder of three people linked to the US consulate 10 days earlier.
Tuesday: newspapers publish a photograph of an alleged drug dealer being arrested by marines next to pictures of a body dressed in the same clothes, which was found dumped on Monday.
Those are just a small selection of incidents from the last five days of Mexico's raging drug wars, which have left few parts of the country untouched over the last three years. A snap visit today by the US secretary of state, Hillary Clinton, defence secretary Robert Gates, and homeland security secretary Janet Napolitano, is a sign of how concerned the US is getting about the growing violence just over its southern border.
With more than 2,000 people killed since the new year, 2010 is shaping up to overtake the record 6,500 drug-related murders last year, which exceeded the toll of more than 5,000 in 2008. The killings have happened despite an offensive against the cartels involving tens of thousands of soldiers and federal police launched in December 2006 by the president, Felipe Calderón.
"We will not take even one step back in the face of those who want to see Mexico on its knees and without a future," Calderón said on Sunday. But such expressions of determination do little to counter the impression that the authorities are unable to deal with the killings, which are marked by ever more inventive cruelty.
At a press conference halfway through the day of meetings, Clinton announced a "new stage" of bilateral co-operation. "We are looking at anything that will work," she said after stressing the end of the previously near exclusive emphasis on security in favour of such issues as sharing financial intelligence.
Clinton would not be drawn into criticising the military-led Mexican offensive but said: "This is not what the military is formed to do and it is something that takes an adjustment."
International coverage focuses on the relentless violence in Ciudad Juárez, which has turned the city into the deadliest in the world, with 191 murders per 100,000 citizens.
But this is a complex and multi-faceted series of regional conflicts involving at least six organised crime groups, which use corruption as well as firepower to control territories.
"The federal government is too weak to control the state governments so it is crazy to think they can control organised crime in those states," said Samuel González, a former drug tsar turned critic of Calderón's military-led strategy.
González said it was illusory to hope that the war would burn itself out through the emergence of a single, clearly dominant cartel. "Every organised crime group has some degree of protection from local authorities, which makes it impossible that one can gain [national] hegemony."
Much of the violence has been between the Sinaloa cartel, led by the country's most famous trafficker, Joaquín "El Chapo" Guzmán, and rivals vying for control of cocaine trafficking corridors across Mexico. The killing is also associated with growing cartel interest in other crime, from the domestic drugs market to kidnapping, arms dealing and people smuggling.
Some of the worst violence recently has been in the north-eastern state of Tamaulipas. The Gulf cartel and its military wing, the Zetas, had assumed terrifying and absolute control over the busiest commercial stretch of frontier in the world. A pax mafiosa – peace between gangs – briefly reigned, with commercial and civic life subjugated by an omnipotent extortion racket.
But over the last month, a battle has exploded in the Gulf cartel. According to reports reaching the Guardian from Reynosa, the centre of the fighting, 200 people were killed over three weeks in February and March.
In Reynosa, at least eight journalists have been kidnapped in recent weeks. Two were visiting reporters from Mexico City who were later released and are too frightened to talk about their ordeal. Another was found tortured to death and five are still missing.
Information from a journalist who must remain nameless for her own safety described armoured cars cruising through Reynosa marked CDG – Cartel del Golfo – or else with the letters XX to denominate the Zetas.
After one gun battle in Reynosa, the Gulf cartel hung a message from a bridge. It read: "Reynosa is a safe city. Nothing is happening or will happen. Keep living your lives as normal. We are part of Tamaulipas and we will not mess with civilians. CDG."
The government has sent in the marines but with little success. A crime reporter from Ciudad Victoria, also in Tamaulipas, told the Guardian that he was on his way to cover a shootout last Thursday when traffickers called his mobile phone and warned him not to publish anything. "They know everything about you. I don't know how, but they do," he said. "If you publish anything about them they don't like, or somebody in the government who is protecting them, then you are going to regret it, big time."
The following day there were five gun battles across the city, and on Saturday there were a further three. Only one was referred to by the state government website that promises reliable information about the violence.
Local news outlets decided against publishing government promises to improve security after warnings from the traffickers. Publishers self-censor complaints of abuses by the army for fear of angering the third force also battling for control of Tamaulipas.
Meanwhile, the axis of the conflict in Juárez is the attempt by El Chapo to muscle in on the turf traditionally controlled by the Juárez cartel.
In the urban nightmare of Juárez,the pyramids of narco-cartel power have collapsed into a state of criminal anarchy. Gangs fight for the local plaza, or dealing turf. Police forces are infested by corruption. The role of the army in Juárez has also been called to account by a state human rights official, Gustavo de la Rosa, who accuses the military of playing a part in "social cleansing".
Amexica: War Along the Borderline, by Ed Vulliamy, is published in September by Bodley Head, London, and Farrar Straus Giroux, New York