ROME -- Italian police are carrying out antiterrorism raids, French officials have reimposed passport checks at borders, and Spain has deployed its army at train stations, power plants, and shopping malls.
Across the continent, authorities are scrambling to step up security to protect their cities after last week's deadly bombings in London stirred new fears that another European country could be the next target of Islamic extremists.
''There's not a single country in the world that's safe from terrorism, including France," President Jacques Chirac of France said yesterday as his country marked the Bastille Day holiday under exceptional security measures.
Amid bomb scares and a general sense of vulnerability, police throughout Europe have increased surveillance around trains and subways, airports, and ports.
European Union officials held emergency talks in Brussels this week and vowed to implement an antiterrorism plan by year's end, including steps to cut off funding to terrorist groups and share more intelligence. Europol, the EU's criminal intelligence agency, said its antiterrorism unit of three dozen was working around the clock on the London attacks.
After the London bombings, France raised its terrorism alert status to the second-highest level of ''red," triggering measures such as increasing the number of soldiers that protect sensitive sites. On Wednesday, France also said it had temporarily suspended the EU's open-border accord and was checking passports at borders with European Union neighbors.
The move prompted calls in some European capitals for other governments to do the same.
Countries that have supported the US-led campaign in Iraq fear they might be targeted for attack. Internet posters have made threats against US allies Denmark and Italy.
The Danish Intelligence Service said it takes the threats ''very seriously." Security has been heightened there, especially on trains and the Copenhagen metro.
Denmark has some 500 troops stationed near Basra in southern Iraq.
Italy has about 3,000, also in southern Iraq, and is expected to start pulling out about 300 soldiers in September.
Italian police carried out raids Wednesday against suspected Islamic extremists in Milan, Rome, and Turin, the host of next year's Winter Olympics. Police questioned 174 people to ascertain their legal status in Italy, and the Interior Ministry said the process might lead to expulsions in some cases.
The raids were carried out a day after Interior Minister Giuseppe Pisanu told parliament that terrorism is ''knocking on Italy's door" and proposed tough antiterrorism measures.
The package, to be approved by parliament, includes allowing authorities to detain suspects longer without charges, giving police greater investigative powers and incentives for those who help to bring down terrorist cells.
The Italian government has stepped up security and is looking into beefed up measures to protect monuments, museums and archeological sites.
In Poland, also a US ally in Iraq, police have received a number of false bomb threats, including one Tuesday that led authorities to evacuate 20,000 people from Warsaw's one-line subway system. A search revealed the threat was a hoax.
Warsaw was looking at its rescue services amid worries over outdated technology, a lack of monitoring cameras in many public areas, and ineffective cooperation among authorities.
The German government has increased security at borders and Interior Minister Otto Schily said this week that security at British installations has been ''a little upgraded."